'Happen' in the Bible

Then Peter took Him aside and began to rebuke Him, “Oh no, Lord! This will never happen to You!”

While He was sitting on the Mount of Olives, the disciples approached Him privately and said, “Tell us, when will these things happen? And what is the sign of Your coming and of the end of the age?”

How, then, would the Scriptures be fulfilled that say it must happen this way?”