Could Abraham know that God is testing him? Or has he simply learned to trust God's instructions? I wonder if obedience is related to relationship, if God desires not mindless obedience so much as trust.
Back in the mid-1990s I wrote a book on sin. Each of us knows sin experientially, of course, but few of us know it comprehensively even in that way because we are parochial even in our sinning. So I had to study sin. For a couple of years I read about sin in the Bible. I read commentaries on the Bible, theological encyclopedia articles and books on virtue and vice.