'Knocks' in the Bible

And if he knocks out the tooth of his male servant or female servant, he must let the servant go free because of [the loss of] the tooth.

For everyone who keeps on asking [persistently], receives; and he who keeps on seeking [persistently], finds; and to him who keeps on knocking [persistently], the door will be opened.

Be like men who are waiting for their master when he returns from the wedding feast, so that when he comes and knocks they may immediately open the door for him.