Charles Ellicott Commentary Isaiah 63:16

"For thou art our Father, though Abraham knoweth us not, and Israel doth not acknowledge us: thou, O Jehovah, art our Father; our Redeemer from everlasting is thy name." — Isaiah 63:16 (ASV)

Doubtless you are our father, though Abraham ... —Better, For Abraham is ignorant of us. The passage is striking as an anticipation of the New Testament thought that the Fatherhood of God rests on something other than hereditary descent, and extends not to a single nation only, but to all mankind.

Abraham might disclaim his degenerate descendants, but Jehovah would still recognise them. Implicitly, at least, the words contain the truth that God is able of these stones to raise up children unto Abraham (Matthew 3:9). He is still their Redeemer.

The words may possibly imply the thought that, as in the case of Jeremiah , and Rachel (Jeremiah 31:15), Abraham was thought of as watching over his posterity and interceding for them. So, eventually, Abraham appears in the popular belief of Israel as welcoming his children in the unseen world (Luke 16:22).