Adam Clarke on Genesis 24:19

I will draw water for thy camels also - Had Rebekah done no more than Eliezer had prayed for, we might have supposed that she acted not as a free agent, but was impelled to it by the absolutely controlling power of God; but as she exceeds all that was requested, we see that it sprang from her native benevolence, and sets her conduct in the most amiable point of view.