'Knock' in the Bible

And I say unto you, Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you.

When once the master of the house is risen up, and hath shut to the door, and ye begin to stand without, and to knock at the door, saying, Lord, open to us; and he shall answer and say to you, I know you not whence ye are;