'Behoveth' in the Bible

And his disciples questioned him, saying, 'Why then do the scribes say that Elijah it behoveth to come first?'

and ye shall begin to hear of wars, and reports of wars; see, be not troubled, for it behoveth all these to come to pass, but the end is not yet.

how then may the Writings be fulfilled, that thus it behoveth to happen?'