Genesis 26:12-15
12 Then Isaac sowed in that land, and received in the same year an hundredfold: and the Lord blessed him.
13 And the man waxed great, and went forward, and grew until he became very great:
14 For he had possession of flocks, and possession of herds, and great store of servants: and the Philistines envied him.
15 For all the wells which his father's servants had digged in the days of Abraham his father, the Philistines had stopped them, and filled them with earth.
Then Isaac sowed. Here Moses proceeds to relate in what manner Isaac reaped the manifest fruit of the blessing promised to him by God; for he says, that when he had sowed, the increase was a hundredfold: which was an extraordinary fertility, even in that land. He also adds, that he was rich in cattle, and had a very great household. Moreover, he ascribes the praise of all these things to the blessing of God; as it is also declared in the psalm, that the Lord abundantly supplies what will satisfy his people while they sleep. (Ps. 127:2) It may, however, be asked, how could Isaac sow when God had commanded him to be a stranger all his life? Some suppose that he had bought a field, and so translate the word kanah a possession; but the context corrects their error: for we find soon afterwards, that the holy man was not delayed, by having land to sell, from removing his effects elsewhere: besides, since the purchasing of land was contrary to his peculiar vocation and to the command of God, Moses undoubtedly would not have passed over such a notable offence. To this may be added, that since express mention is immediately made of a tent, we may hence infer, that wherever he might come, he would have to dwell in the precarious condition of a stranger. We must, therefore, maintain, that he sowed in a hired field. For although he had not a foot of land in his own possession, yet, that he might discharge the duty of a good householder, it behoved him to prepare food for his family; and perhaps hunger quickened his care and industry, that he might with the greater diligence make provision for himself against the future. Nevertheless, it is right to keep in mind, what I have lately alluded to, that he received as a divine favour the abundance which he had acquired by his own labour.
It was not, however, a slight trial, that the simple element of water, which is the common property of all animals, was denied to the holy patriarch; with how much greater patience ought we to bear our less grievous sufferings!
And the Philistines envied him. We are taught by this history that the blessings of God which pertain to the present earthly life are never pure and perfect, but are mixed with some troubles, lest quiet and indulgence should render us negligent. Wherefore, let us all learn not too ardently to desire great wealth. If the rich are harassed by any cause of disquietude, let them know that they are roused by the Lord, lest they should fall fast asleep in the midst of their pleasures; and let the poor enjoy this consolation, that their poverty is not without its advantages. For it is no light good to live free from envy, tumults, and strifes. Should any one raise the objection, that it can by no means be regarded as a favour, that God, in causing Isaac to abound in wealth, exposed him to envy, to contentions, and to many troubles; there is a ready answer, that not all the troubles with which God exercises his people, in any degree prevent the benefits which he bestows upon them from retaining the taste of his paternal love. Finally, he so attempers the favour which he manifests towards his children in this world, that he stirs them up, as with sharp goads, to the consideration of a celestial life. It was not, however, a slight trial, that the simple element of water, which is the common property of all animals, was denied to the holy patriarch; with how much greater patience ought we to bear our less grievous sufferings! If, however, at any time we are angry at being unworthily injured; let us remember that, at least, we are not so cruelly treated as holy Isaac was, when he had to contend for water. Besides, not only was he deprived of the element of water, but the wells which his father Abraham had dug for himself and his posterity were filled up. This, therefore, was the extreme of cruelty, not only to defraud a stranger of every service due to him, but even to take from him what had been obtained by the labour of his own father, and what he possessed without inconvenience to any one.
— John Calvin (1509-1564)