It is not unjust for God to choose to use certain groups or certain people for His purposes in this world – His choice in either case is not tied to the worthiness of the group or individual, but to His own good plan. To understand how such action on God’s part is not unjust, we must learn to distinguish between “positional hardening” and “personal hardening”. As Prov. 21:1 makes plain, the heart of a king is “water in the hands of the Lord”, and God will work to bring about the decisions He desires through their positions (even such hardening). But when it comes to a personal decision to respond to God, God does not harden a person, although a refusal to believe can lead to increasing spiritual hardness in a person.