You are talking scripture out of context and avoiding the pertinent information which I detailed in several posts that shows he was tithing to a priest.
Second it does NOT say the King didn't want a tenth. It says Abraham gave him a tenth THEN of the possessions that belonged to the King of Salem the king said Abraham could keep what he recovered except the persons and Abraham refused to take it.
You are confusing two different sets of circumstances because you are talking scripture out of context
It does NOT say Abraham gave a tenth to both kings
Gen 14:18 And Melchizedek king of Salem brought out bread and wine. (He was priest of God Most High.)
Gen 14:19 And he blessed him and said, "Blessed be Abram by God Most High, Possessor of heaven and earth;
Gen 14:20 and blessed be God Most High, who has delivered your enemies into your hand!"
And Abram gave him a tenth of everything.
HIM not THEM. It was NOT directed to both kings but ONE King.
Gen 14 tells us that.
Hebrews 7 confirms.
Scripture out of context is pretext. READ THE CONTEXT ALWAYS
Gen 14:18 And Melchizedek king of Salem brought out bread and wine. (He was priest of God Most High.)
Gen 14:19 And he blessed him and said, "Blessed be Abram by God Most High, Possessor of heaven and earth;
Gen 14:20 and blessed be God Most High, who has delivered your enemies into your hand!" And Abram gave him a tenth of everything.
Gen 14:21 And the king of Sodom said to Abram, "Give me the persons, but take the goods for yourself."
Gen 14:22 But Abram said to the king of Sodom, "I have lifted my hand to the LORD, God Most High, Possessor of heaven and earth,
Gen 14:23 that I would not take a thread or a sandal strap or anything that is yours, lest you should say, 'I have made Abram rich.'
When you read the context way way back you find that the king Abraham defeated had taken the possessions of Lot and the king of Sodom and the king was speaking of those possessions that belonged to him
Gen 14:11 So the enemy took all the possessions of Sodom and Gomorrah, and all their provisions, and went their way.
Abraham was returning the goods and the people and the King of Sodom was thankful enough to let Abraham keep the goods
Two different events. King of Salem/Tithe. King of Sodom, return of goods