'Knock' in the Bible

She is empty, void, and waste. The heart melts, the knees knock together, their bodies and faces have grown pale.

"Ask, and it will be given you. Seek, and you will find. Knock, and it will be opened for you.

When once the master of the house has risen up, and has shut the door, and you begin to stand outside, and to knock at the door, saying, 'Lord, Lord, open to us!' then he will answer and tell you, 'I don't know you or where you come from.'

Behold, I stand at the door and knock. If anyone hears my voice and opens the door, then I will come in to him, and will dine with him, and he with me.