Hebrews 7:1
For this Melchisedec, king of Salem, priest of the most high God, who met Abraham returning from the slaughter of the kings, and blessed him; For this Melchisedec, king of Salem, priest of the most high God, who met Abraham returning from the slaughter of the kings, and blessed him;
For this Melchisedec is king of Salem and priest of the most high God, who met Abraham returning from the slaughter of the kings and blessed him. Salem means peace, so Melchisedek is the King of Peace, and Melchisedek is Jesus Christ. He was God's witness on earth who represented the Lord Jesus Christ in person to reveal the truth of heaven and perpetuate the law of God. Abraham's encounter with Melchizedek testifies to who Jesus is, so that Abraham would be named when the question is asked to identify Jesus. That testimony identifies Jesus as the Messiah, the Prince of Life and the Redeemer of the world. That testimony identifies the One entering Jerusalem with a vast company of followers as that promised King of Peace.
Abraham gave tithes to Melchizedek, the priest of the Most High God. The meeting belongs to the patriarchal age and shows that giving to God for religious purposes and the duty to return tithes existed before Moses and the Mosaic tithing system and was practiced in Abraham's time and was not a later requirement. Those living under the Melchizedek priesthood as Christians have the same duty to tithe.