Genesis 12-14

After the defeat of the kings who had captured Lot Abram was offered two gifts. Two kings offered him a reward at the end of the battle. Bera, king of Sodom, was so thankful for the victory that he saw Abram attain that he offered him all of the spoils of the campaign. Bera felt that Abram had earned that prize. The offer from Melchizedek was a memorial meal, a blessing in God's name, and a proclamation of God's victory through Abram's effort.  Abram assessed the gifts he was offered and considered them in light of God's earlier promises. The gist that gave all the glory to God  and demonstrated his grace he chose to accept. He refused the gift that was the best of this world. Even though Abram had seen only a small portion of God's promises fulfilled he held fast to that which is eternal over the temporary things of this world.
Stuart