Rashi on Genesis 14:23/רש"י על בראשית י״ד:כ״ג

1אם מחוט ועד שרוך נעל NOT ANYTHING FROM A THREAD EVEN TO A SANDAL TIE shall I retain for myself from the spoil.

2ואם אקח מכל אשר לך NOR ANYTHING THAT IS THINE WILL I TAKE — And if you say that you will reward me from your own treasures I will still not accept anything

3'ולא תאמר וגו SO THAT THOU SHOULDST NOT SAY etc. — For the Holy One, blessed be He, has promised to give me riches, as it is said, (Genesis 12:2) “And I will bless thee” (see Rashi on this passage, where the blessing is explained to consist in ממון “wealth”).