In its deeper layers, Jesus' Parable of the Sower presents not differences between people but different kinds of terrain within each of us. Those who see are those who stand before Jesus and know that we all contain such variety.
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.
From this side of history, Jeremiah has great resolve. Yet the shifting political allegiances he interprets are not so different from our own uncertainties. Only in retrospect are Jeremiah's claims clear.