godsend
n.something that is extremely helpful or welcome, especially when you are in a difficult situation. You use this to describe a person or thing that saves you from a problem.
n.a person or thing that provides great relief or assistance, especially in a time of crisis. Often used to describe a sudden solution to a difficult problem.
“The rain was a godsend after such a long, dry summer.”
“Finding a parking spot right in front of the building was a godsend on such a busy Friday afternoon.”
“The sudden arrival of the rescue team was a godsend for the stranded hikers, who had been running low on water and daylight for hours.”
A variant of God’s send, from God + -’s + send (“(obsolete) act of sending”), in the sense of someone or something sent by God.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.