As a convert, I hear this a lot:
Masha Allah, also Masha'Allah, is an Arabic phrase that means "God has willed", expresses appreciation, joy, praise, or thankfulness for an event or person that was just mentioned. -- Mashallah
While the Wikipedia page lists the etymology of the word, it doesn't address where usage of this word originated.
Question: How did saying Mashallah originate?
I found this YouTube video, which I can't see at the moment, but Zaid mentioned in chat it's not suitable.