Genesis 20:1

1.And Abraham journeyed from thence. What Moses related respecting the destruction of Sodom, was a digression. He now returns to the continuation of his history, and proceeds to show what happened to Abraham; how he conducted himself, and how the Lord protected him; till the promised seed, the future source of the Church, should be born unto him. He also says, that Abraham came into the South country; not that he traveled beyond the limits of the inheritance given to him, but left his former abode, and went towards the South. Moreover; the region which he points out fell chiefly, afterwards, to the lot of the tribe of Judah. It is, however, unknown what was his intention in removing, or what necessity impelled him to change his place: we ought, however, to be persuaded, that he had not transferred his abode to another place for any insufficient cause; especially since a son, whom he had not even dared to wish for, had been lately promised him, through Sarah. Some imagine that he fled from the sad spectacle which was continually presented before his eyes; for he saw the plain, which had lately appeared so pleasant to the view, and so replenished with varied abundance of fruits, transformed into a misshapen chaos. And certainly, it was possible that the whole neighborhood might be affected with the smell of sulphur, as well as tainted with other corruptions, in order that men might the more clearly perceive this memorable judgment of God. Therefore, there is nothing discordant with facts, in the supposition, that Abraham, seeing the place was under the curse of the Lord, was, by his detestation of it, drawn elsewhere. It is also credible, that (as it happened to him in another place) he was driven away by the malice and injuries of those among whom he dwelt. For the more abundantly the Lord had manifested his grace towards him, the more necessary was it, in return, for his patience to be exercised, in order that he might reflect upon his conditions as a pilgrim upon earth. Moses also expressly declares, that he dwelt as a stranger in the land of Gerar. Thus we see, that this holy family was driven hither and thither as refuse, while a fixed abode was granted to the wicked. But it is profitable to the pious to be thus unsettled on earth; lest, by setting their minds on a commodious and quiet habitation, they should lose the inheritance of heaven.