godsend

noun

Etymology: A variant of God’s send, from God + -’s + send (“(obsolete) act of sending”), in the sense of someone or something sent by God.

1. An instance of unexpected benefit or good fortune; a windfall.

   “"You do, indeed, seem to take it to heart!" exclaimed the actress, an expression of jealous anger crossing her features; "why, it is quite a God-send for you! many a heart is caught in the rebound.[…]"”

   “[O]nce again, as in 1803, we were on the brink of being sacrificed to the very lunacies of retrenchment. By a mere god-send, more troops happened to arrive from the Indian continent.”

2. An instance of unexpected benefit or good fortune; a windfall.

   “Its seldom sic [such] rich Godsends come on our coast—no since the Jenny and James came ashore in King Charlie's time.”

3. A person who provides greatly needed assistance.