'Watchman' in the Bible

For thus hath the Lord said unto me, Go, set a watchman, let him declare what he seeth.

And the lookout called like a lion,“O Lord, I stand continually on the watchtower by day,And I am stationed every night at my guard post.

“Now look! Here comes a troop of riders, horsemen in pairs.”And one said, “Fallen, fallen is Babylon;And all the carved images of her gods are shattered on the ground.”

The burden of Dumah. He calleth to me out of Seir, Watchman, what of the night? Watchman, what of the night?

The watchman said, The morning cometh, and also the night: if ye will inquire, inquire ye: return, come.