Every man struggles with his faith and every child of God ultimately follows his heavenly Father in fits and starts.
Abraham believes God and God justifies him. Salvation is always by faith.
God cannot be unfaithful.
God works His plan through man’s actions whether they are righteous or sinful.
The story of Abram marks the beginning of God’s specific plan of redemption.
The flood is over but sin remains, so the only solution is to provide for its death.