The servant has arrived. He is standing at the well outside the city of Nachor, and he has to figure out, in a single afternoon, which woman at that well is meant to become the mother of a nation. So he prays a prayer so audacious that it almost sounds like a wager.
"Let the damsel to whom I say, Reach me now thy pitcher, that I may drink, and she say, Drink, and I will also make my camels drink — be she whom Thou hast provided to go to Thy servant Isaac" (Genesis 24:14). Targum Pseudo-Jonathan preserves the servant's careful wording: he is not asking for a sign of beauty or wealth. He is asking for a sign of character.
Look at the math. Ten camels have just crossed a desert. A thirsty camel can drink twenty-five gallons. That is roughly two hundred and fifty gallons of water the offering girl would have to draw, one pitcher at a time, for strangers. A woman who says yes to that request has passed a test no poetry could measure.
The servant, taught by Abraham, knew what his master's house was built on. Not wealth. Not bloodline. Chesed — lovingkindness done for a stranger who cannot repay you. So he designs a test in the shape of chesed, and trusts that the God who loves chesed will answer in kind.
This is why the sages loved this moment. The servant did not ask for a miracle. He asked for a window into someone's soul. And he trusted God to arrange the rest.