Some blessings are said with eyes closed. This one was said with eyes wide open. The servant has just discovered that the girl who watered his ten camels is also the grand-niece of his master, a daughter of the very household Abraham sent him to find. And he bows, there at the well, and speaks a line of praise Targum Pseudo-Jonathan preserves with surgical precision (Genesis 24:27).
"Blessed be the Name of the Lord, the God of my master Abraham, who hath not restrained His mercy and His truth from my master." The Targum pairs two words — chesed v'emet, mercy and truth — and refuses to let them drift apart. Mercy is the extravagant gift. Truth is the kept promise.
The servant understood the difference. Mercy would have been finding any suitable wife. Truth was finding this wife, from this family, because Abraham had sworn an oath against marrying Isaac into Canaanite lineage (Genesis 24:3). God had done both at once — the generous thing and the exact thing.
Notice the phrase that follows: "for the sake of his righteousness, in the right way hath the Lord led me to the house of my master's brother." The Targum gives the servant a theology in two clauses. First, Abraham's righteousness is the reason the road opened. Second, the road was straight the whole time — he only saw its straightness from the far end.
This is a prayer for people who look back on a hard journey and suddenly see the hand that steadied it. Say it when you arrive. Say it when you finally understand what you were being led toward.