In the case of Melchizedek receiving tithes from Abraham, that is not true. Here was someone who was clearly nothing to do with the family of Abraham, for unlike the Levites he was not descended from Abraham but lived as a contemporary of Abraham, and yet he received tithes of the patriarch.
The Scriptures which cannot be broken set all things in their proper order. They correct our thinking constantly if we have gone off track, so that we see the most important things as God sees them. Abraham was a great man with great privileges given him by God, but greater far is the Lord Jesus Christ, the Messiah. He is the real one that we should cling to, for he gives us life and he is high above any fallen man, even though that man plays a prominent part in the plan of God. Christ is the perfect one who alone is worthy of praise, and who because he is the eternal Son of God is also worthy of worship.