17:1 It has been 13 years since Abram hearkened to Sarah in unbelief.
13 typifies unbelief or rebellion, for example 14:4 "in the 13th year they
rebelled".
Noah and Enoch walked with God (5:24,6:9) as friends.
Abraham is bidden to walk before Me as a child.
Israel is told to walk behind Me (Deuteronomy 13:4) as a servant.
The Church is told to walk in Him (Colossians 2:6) in union.
"Be thou perfect" - entire, whole, no longer compromised by
the expedients of unbelief. Matthew 5:48