I had not thought to see thy face - There is much delicacy and much tenderness in these expressions. He feels himself now amply recompensed for his long grief and trouble on account of the supposed death of Joseph, in seeing not only himself but his two sons, whom God, by an especial act of favor, is about to add to the number of his own. Thus we find that as Reuben and Simeon were heads of two distinct tribes in Israel, so were Ephraim and Manasseh; because Jacob, in a sort of sacramental way, had adopted them with equal privileges to those of his own sons.

And Israel said unto Joseph, I had not thought to see thy face,.... Some years ago he never expected to have seen him any more; he had given him up for lost, as a dead man, when his sons brought him his coat dipped in blood; and by reason of the long course of years which passed before ever he heard anything of him:
and, lo, God hath showed me also thy seed; it was an additional favour to see his offspring; it can hardly be thought, that in a course of seventeen years he had been in Egypt, he had not seen them before, only he takes this opportunity, which was the last he should have of expressing his pleasure on this occasion.

I had not thought to see thy face, (having many years given him up for lost) and lo God hath shewed me also thy seed? - See here, How these two good men own God in their comforts. Joseph saith, They are my sons whom God has given me - And to magnify the favour he adds, in this place of my banishment, slavery and imprisonment. Jacob saith here, God hath shewed me thy seed - Our comforts are then doubly sweet to us, when we see them coming from God's hand.