Genesis 26:1 There was a famine in the land, besides the first famine that was in the days of Abraham. And Isaac went to Abimelech king of the Philistines, in Gerar.
“As we know not the time when the famine happened, so we cannot tell whether this was the same Abimelech, Phichol, etc., which are mentioned Gen 20:1, Gen 20:2, etc., or the sons or other descendants of these persons.” (Adam Clarke) "The present king of this place can scarce be thought to be the same Abimelech that was king of it in Abraham's time; but it is highly probable that this Abimelech was the son of the former king, and that this was a common name to the kings of Gerar or the Philistines, as Pharaoh was to the kings of Egypt. “ (Gill’s Exposition) Nevertheless, we know that they were a people in covenant with the Hebrews.
2 Then the Lord appeared to him and said: “Do not go down to Egypt; live in the land of which I shall tell you. 3 Dwell in this land, and I will be with you and bless you; for to you and your descendants I give all these lands, and I will perform the oath which I swore to Abraham your father. 4 And I will make your descendants multiply as the stars of heaven; I will give to your descendants all these lands; and in your seed all the nations of the earth shall be blessed; 5 because Abraham obeyed My voice and kept My charge, My commandments, My statutes, and My laws.”
I do not know whether it as a physical manifestation or the still small voice of the past. "Only once besides does Jehovah manifest himself to Isaac (Genesis 26:24), and sixty years had now passed since the revelations recorded in Genesis 22. Excepting to Abraham, it was only at rare and distant intervals that God spake to the patriarchs. The greater part of their lives was spent under the control of the same ordinary Providence as that which governs our actions now; but on special occasions God was pleased to confirm their faith in Him in a way not necessary now that we have had made known to us the whole counsel of God.” (Benson Commentary)
Isaac was not told to stay in Gerar trusting is an ally— only not to got to Egypt for sustenance. Simularly, the servant of Abraham was commanded not to take him back to Haran for a wife (Gen 24:5). Three options appear here: Egypt, Gerar, and Yahweh only.
By nature, “Egypt could offer him more than the impoverished land in which he and the Philistines were living but while he was weighing the pros and cons the Lord gave him some straightforward instructions, forbidding him to enter into a relationship with the Egyptians… he was being asked to trade immediate solutions to a serious problem for a promise which was nowhere near as tangible.” (The Preacher’s Commentary) But this situation had spiritual element. Would the patriarch trust in riches and the seeing of the eyes? or would he trust in Yahweh his God only?
"The trials which meet God's people, in their course, are very much like; and they ever tend to make manifest how far the heart has found its all in God. It is a difficult matter — a rare attainment, so to walk in sweet communion with God as to be rendered thereby entirely independent of things and people here. The Egypts and the Gerars which lie on our right hand and on our left present great temptations, either to turn aside out of the right way, or to stop short of our true position as servants of the true and living God.” (C. H. Mackintosh's Notes on the Pentateuch)
6 So Isaac dwelt in Gerar.
Total dependence on Yahweh in the land was a third option. But it is acknowledged:
“There is a manifest difference between Egypt and Gerar. Egypt is the expression of the world in its natural resources, and its independence of God. 'My river is mine own,' is the language of an Egyptian who knew not Jehovah, and thought not of looking to Him for ought. Egypt was, locally, further removed from Canaan than Gerar; and, morally, it expresses a condition of soul further from God.” (C. H. Mackintosh's Notes on the Pentateuch) Isaac passed but got a low grade.
7 And the men of the place asked about his wife. And he said, “She is my sister”; for he was afraid to say, “She is my wife,” because he thought, “lest the men of the place kill me for Rebekah, because she is beautiful to behold.” 8 Now it came to pass, when he had been there a long time, that Abimelech king of the Philistines looked through a window, and saw, and there was Isaac, showing endearment to Rebekah his wife. 9 Then Abimelech called Isaac and said, “Quite obviously she is your wife; so how could you say, ‘She is my sister’?”
Isaac said to him, “Because I said, ‘Lest I die on account of her.’”
10 And Abimelech said, “What is this you have done to us? One of the people might soon have lain with your wife, and you would have brought guilt on us.” 11 So Abimelech charged all his people, saying, “He who touches this man or his wife shall surely be put to death.”
Thankfully, like the man who dealt with Abraham, this Abimelech seems to be a righteous man, obeying and enforcing the commandments of God. "In the Biblical account of Abraham’s family, the iniquity of deception became a stronghold that affected the lives of Abraham, Isaac, Jacob, and Jacob’s sons. (See Gen 12:10–20, 20, 26:1–11, 27:1–40, 37:12–36.…
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When we understand how our lives are influenced by our forefathers, we can respond appropriately to that influence. We should appreciate and celebrate the good that has been passed down through our families. Also, we should acknowledge the iniquities of our forefathers, repent of our own sins, and endeavor to overcome the tendencies toward specific sins that we have inherited. While we are not held responsible for the sins of our ancestors, we are susceptible to their areas of weakness and should be alert to these inclinations…
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When God gave the Ten Commandments to the nation of Israel, He included this description of His character and ways: '. . . I the Lord thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me; and showing mercy unto thousands of them that love me, and keep my commandments' (Exo 20:5–6). God repeats this warning about generational iniquities in Exo 34:6–7, Num 14:18, and Deut 5:9–10…
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The power to overcome generational sins comes only by Jesus Christ. The Apostle Paul encourages us, 'Put ye on the Lord Jesus Christ, and make not provision for the flesh, to fulfill the lusts thereof' (Rom 13:14). Jesus said: 'Verily, verily, I say unto you, Whosoever committeth sin is the servant of sin. And the servant abideth not in the house forever: but the Son abideth forever. If the Son therefore shall make you free, ye shall be free indeed” (John 8:34–36).’"
http://iblp.org/questions/how-do-sins-my-forefathers-affect-my-life
Genesis 26:12 Then Isaac sowed in that land, and reaped in the same year a hundredfold; and the Lord blessed him. 13 The man began to prosper, and continued prospering until he became very prosperous; 14 for he had possessions of flocks and possessions of herds and a great number of servants. So the Philistines envied him. 15 Now the Philistines had stopped up all the wells which his father’s servants had dug in the days of Abraham his father, and they had filled them with earth. 16 And Abimelech said to Isaac, “Go away from us, for you are much mightier than we.”
17 Then Isaac departed from there and pitched his tent in the Valley of Gerar, and dwelt there.
The Philistines were supposed to be allies of the Hebrews; but oh how fickle is the human spirit, even among brethren. "The Philistines’ envy was very natural, since Isaac was an alien, and, in some sense, an intruder. Their stopping of the wells was a common act of hostility, and an effectual one in that land, where everything lives where water comes, and dies if it is cut off. Abimelech’s reason for ‘extraditing’ Isaac might have provoked a more pugnacious person to stay and defy the Philistines to expel him. ‘Thou art much mightier than we,’ and so he could have said, ‘Try to put me out, then,’ and the result might have been that Abimelech and his Philistines would have been the ones to go. But the same spirit was in the man as had been in the lad, when he let his father bind him and lay him on the altar without a struggle or a word, and he quietly went, leaving his fields and pastures. ‘Very poor-spirited,’ says the world; what does Christ say?” (Alexander MacLauren, Expositions of Holy Scripture)
Mathew 5:1-11 "And seeing the multitudes, He [Jesus] went up on a mountain, and when He was seated His disciples came to Him. Then He opened His mouth and taught them, saying:
'Blessed are the poor in spirit, for theirs is the kingdom of heaven.
Blessed are those who mourn, for they shall be comforted.
Blessed are the meek, for they shall inherit the earth.
Blessed are those who hunger and thirst for righteousness, for they shall be filled.
Blessed are the merciful, for they shall obtain mercy.
Blessed are the pure in heart, for they shall see God.
Blessed are the peacemakers, for they shall be called sons of God.
Blessed are those who are persecuted for righteousness’ sake, for theirs is the kingdom of heaven.
Blessed are you when they revile and persecute you, and say all kinds of evil against you falsely for My sake. Rejoice and be exceedingly glad, for great is your reward in heaven, for so they persecuted the prophets who were before you.’"
18 And Isaac dug again the wells of water which they had dug in the days of Abraham his father, for the Philistines had stopped them up after the death of Abraham. He called them by the names which his father had called them.
19 Also Isaac’s servants dug in the valley, and found a well of running water there. 20 But the herdsmen of Gerar quarreled with Isaac’s herdsmen, saying, “The water is ours.” So he called the name of the well Esek, [Literally Quarrel] because they quarreled with him. 21 Then they dug another well, and they quarreled over that one also. So he called its name Sitnah. [Literally Enmity]
22 And he moved from there and dug another well, and they did not quarrel over it. So he called its name Rehoboth,[Literally Spaciousness] because he said, “For now the Lord has made room for us, and we shall be fruitful in the land.”
23 Then he went up from there to Beersheba. 24 And the Lord appeared to him the same night and said, “I am the God of your father Abraham; do not fear, for I am with you. I will bless you and multiply your descendants for My servant Abraham’s sake.”
25 So he built an altar there and called on the name of the Lord, and he pitched his tent there; and there Isaac’s servants dug a well.
Excerpt from Alexander MacLauren, Expositions of Holy Scripture
"Isaac was not ‘original.' He cleaned out the wells which his father had digged, and with filial piety gave them again the old names ‘which his father had called them.’ Some of us nowadays get credit for being 'advanced and liberal thinkers,’ because we regard our fathers’ wells as much too choked with rubbish to be worth clearing out, and the last thing we should dream of would be to revive the old names. But the old wells were not enough for the new time, and so fresh ones were added. Isaac and his servants did not say, 'We will have no water but what is drawn from Abraham’s wells. What was enough for him is enough for us.' So, like all wise men, they were conservatively progressive and progressively conservative. The Gerar shepherds were sharp lawyers. They took strong ground in saying, 'The water is ours; you have dug wells, but we are ground-owners, and what is below the surface, as well as what is on it, is our property.' Again Isaac fielded, moved on a little way, and tried again. A second well was claimed, and given up, and all that Isaac did was to name the two ‘Contention’ and ‘Enmity,’ as a gentle rebuke and memorial. Then, as is generally the result, gentleness wearied violence out, and the Philistines tired of annoying before Isaac tired of yielding. So he came into a quiet harbour at last, and traced his repose to God, naming his last well ‘Broad Places,’ because the Lord had made room for him.
Such a quiet spirit, strong in non-resistance, and ready to yield rather than quarrel, was strangely out of place in these wild days and lands. He obeyed the Sermon on the Mount millenniums before it was spoken. Whether from temperament or from faith, he is the first instance of the Christian type of excellence in the Old Testament. For there ought to be no question that the spirit of meekness, which will not meet violence by violence, is the Christian spirit. Christian morals alter the perspective of moral excellences, and exalt meekness above the ‘heroic virtues’ admired by the world. The violets and lilies in Christ’s garden outshine voluptuous roses and flaunting sunflowers. In this day, when there is a recrudescence of militarism, and we are tempted to canonise the soldier, we need more than ever to insist that the highest type is ‘the Lamb of God,’ who was ‘as a sheep before her shearers.’ To fight for my rights is not the Christian ideal, nor is it the best way to secure them. Isaac will generally weary out the Philistines, and get his well at last, and will have escaped much friction and many evil passions.
‘Tis safer being meek than fierce.’
Isaac won the friendship of his opponents by his patience, as the verses after the text tell. Their consciences and hearts were touched, and they ‘saw plainly that the Lord was with him,’ and sued him for alliance. It is better to turn enemies into friends than to beat them and have them as enemies still. ‘I’ll knock you down unless you love me’ does not sound a very hopeful way of cementing peaceful relations. But ‘when a man’s ways please the Lord, he maketh even his enemies to be at peace with him.’ But Isaac won more than the Philistines’ favour by his meek peacefulness, for ‘the Lord appeared unto him,’ and assured him that, undefended and unresisting as he was, he had a strong defence, and need not be afraid: ‘Fear not, for I am with thee.’ The ornament of a meek and quiet spirit is, in the sight of God, of great price, and that not only for ‘a woman’; and it brings visions of God, and assurances of tranquil safety to him who cherishes it. The Spirit of God comes down in the likeness of a dove, and that bird of peace sits ‘brooding ONLY on the charmed wave’ of a heart stilled from strife and wrath, like a quiet summer’s sea.
Isaac’s new home at Beersheba, having been thus hallowed by the appearance of the Lord, was consecrated by the building of an altar. We should hallow by grateful remembrance the spots where God has made Himself known to us. The best beginning of a new undertaking is to rear an altar. It is well when new settlers begin their work by calling on the name of the Lord. Beersheba and Plymouth Rock are a pair. First comes the altar, then the tent can be trustfully pitched, but ‘except the Lord build the house, they labour in vain that build it.’ And if the house is built in faith, a well will not be lacking; for they who ‘seek first the kingdom of God’ will have all needful ‘things added unto them.’” (Alexander MacLauren)
Genesis 26:26 Then Abimelech came to him from Gerar with Ahuzzath, one of his friends, and Phichol the commander of his army. 27 And Isaac said to them, “Why have you come to me, since you hate me and have sent me away from you?”
Isaac "clearly felt his friendship had been betrayed. Now he was puzzled as to why they were approaching him. Because of his friendly nature he did not consider that they were safeguarding their backs.” (Peter Pett)
28 But they said, “We have certainly seen that the Lord is with you. So we said, ‘Let there now be an oath between us, between you and us; and let us make a covenant with you, 29 that you will do us no harm, since we have not touched you, and since we have done nothing to you but good and have sent you away in peace. You are now the blessed of the Lord.’”
"They remembered Yahweh the God of Abraham and they see He is now Isaac’s God and effective on his behalf… The result is that they want a treaty sealed by an oath, just as they had had with Abraham, a treaty of peace and mutual recognition. Isaac may not be Abraham but he is still to be… [revered] because he is the chosen of Yahweh…” (Peter Pett)
"Let there be now an oath.—The word literally signifies a curse. Each side uttered an imprecation, with the prayer that it might fall upon himself if he broke the terms of the covenant. Let us make a covenant.—Heb., cut. (See Note on Genesis 15:10; Genesis 15:18...)” (Ellicott's Commentary)... by innocent sacrifice, just as Abraham had seen regarding his covenant with Yahweh by vision with only manifestations of God ratifying the same. When Yahweh could swear by no greater, He sware by Himself (Hebrews 6:13).
30 So he made them a feast, and they ate and drank. 31 Then they arose early in the morning and swore an oath with one another; and Isaac sent them away, and they departed from him in peace.
"Let us imitate Isaac's goodness; let us imitate his purity, as he was certainly a good virtuous man, devoted to God... He did not return evil for evil. He yielded to those who drove him out, but he receive them again when they were sorry, being neither harsh to insolence nor obdurate to kindness. When he went away from others, he fled to avoid strife. When he received them again, he readily forgave them, and he was exceptionally kind when he pardoned.” (Ambrose)... and renewed the covenant between their peoples.
32 It came to pass the same day that Isaac’s servants came and told him about the well which they had dug, and said to him, “We have found water.” 33 So he called it Shebah.[Literally Oath or Seven] Therefore the name of the city is Beersheba[Literally Well of the Oath or Well of the Seven] to this day.
After cutting covenant with the weaker tribe, the Hebrews found water. Abraham had given the place the name, "Because these seven ewes you will take away from me: in return you will be my witness, that I did dig this well (Be-er). And because of this the place is called Be-er Sheva' (Beersheba) because there the two of them did swear an oath (Shvu'a).” But this event recorded in Genesis 21:31 was "now buried in oblivion, as his wells were; and the wells being revived, he revives and renews the name, which proved now a lasting name, unto this day, as here follows, which is not added Genesis 21:31, because then the name, though given by Abraham, was soon forgotten and neglected by others." (Matthew Poole's Commentary) "The relation, of which the name Beer-sheba was the memorial, had ceased to exist. But by the repetition of the fact, the name regained its significance and power, and was the same as if now given for the first time.” (Hengstenberg) Likewise, the wells of the church fathers are neglected by the masses. Let us endeavor to re-dig these spiritual wells that the Name of above every name might be called upon again in the land, causing many folks to drink thereof.
34 When Esau was forty years old, he took as wives Judith the daughter of Beeri the Hittite, and Basemath the daughter of Elon the Hittite. 35 And they were a grief of mind to Isaac and Rebekah.
Esau had proved that he was concerned with earthly matters. He desired to make a name for himself among the princes of the earth. "The fathers of these two women are represented by Josephus as men of great power and authority among the Canaanites, as very probably they were.” (Gill's Exposition of the Entire Bible) "If the pious feelings of Abraham recoiled from the idea of Isaac forming a matrimonial connection with a Canaanitish woman [Gen 24:3], that devout patriarch himself would be equally opposed to such a union on the part of his children; and we may easily imagine how much his pious heart was wounded, and the family peace destroyed, when his favorite but wayward son brought no less than two idolatrous wives among them—an additional proof that Esau neither desired the blessing nor dreaded the curse of God.’ (Jamieson-Fausset-Brown) And again, "Esau was foolish in marrying two wives together, and still more in marrying Canaanites, strangers to the blessing of Abraham, and subject to the curse of Noah. It grieved his parents that he married without their advice and consent. It grieved them that he married among those who had no religion. Children have little reason to expect God's blessing who do that which is a grief of mind to good parents.” (Matthew Henry)