John Wesley on Genesis 14:22

I have lift up mine hand to the Lord that I will not take anything - Here Observe, The titles he gives to God, the most high God, the possessor of heaven and earth - The same that Melchizedek had just now used. It is good to learn of others how to order our speech concerning God, and to imitate those who speak well in divine things. The ceremony used in this oath; I have lift up my hand - In religious swearing we appeal to God's knowledge of our truth and sincerity, and imprecate his wrath if we swear falsely; and the lifting up of the hands is expressive of both. Lest thou shouldst say, I have made Abram rich - Probably, Abram knew the king of Sodom to be a proud and scornful man, and one that would be apt to turn such a thing as this to his reproach afterwards, and when we have to do with such men, we have need to act with particular caution.