What does Genesis 24:21 mean?

Abraham's servant has come to a city in Mesopotamia named after one of Abraham's relatives (Genesis 22:20–23). His quest is to find a suitable wife for Abraham's son, Isaac (Genesis 24:3–4). To fulfill this request, the servant prayed that God would send a woman with a generous spirit. This would be shown if the servant asked for water, and a woman responded by offering to also bring water for his ten camels (Genesis 24:12–14).

As shown in this verse, God has answered the servant's request so quickly that he is left speechless. Or perhaps he is resisting the urge to decide too hastily that a wife has been found for his master's son. The fact that Rebekah arrived before he has even finished his prayer (Genesis 24:15) seems too good to be true. The servant is clearly loyal to Abraham, and he wants to be sure this is actually the right woman for his master's son. Had the Lord truly granted success in this quest so quickly? Is this really the girl God means for Isaac to marry?

Abraham's servant ponders this while Rebekah completes the lengthy process of carrying water, one jar at a time, to a trough until ten thirsty camels have had their fill.