'Happen' in the Bible

They were still on the road going up to Jerusalem, and Jesus was walking ahead of them; they were full of wonder, and some, though they followed, did so with fear. Then, once more calling to Him the Twelve, He began to tell them what was about to happen to Him.

In solemn truth I tell you that if any one shall say to this mountain, 'Remove, and hurl thyself into the sea,' and has no doubt about it in his heart, but stedfastly believes that what he says will happen, it shall be granted him.

Take care, be on the alert, and pray; for you do not know when it will happen.