Hi Tuan,
A grammarian can give you the technical explanation.
As a native speaker, I can respond to part of your post. The sentence, as it stands, is grammatically correct. It would also be acceptable to write, "Fire is a divine gift that is randomly delivered in the form of lightning." The writer might have written 'that was' to suggests that the divine gift was randomly delivered in the past, but that's not the idea, since lightning continues throughout time, and will always be what it is--now, in the past, and forevermore.
You application, 'This is a book made in England', is correct.