'Knocking' in the Bible

“I was asleep but my heart was awake.A voice! My beloved was knocking:‘Open to me, my sister, my darling,My dove, my perfect one!For my head is drenched with dew,My locks with the damp of the night.’

She is emptied! Yes, she is desolate and waste!Hearts are melting and knees knocking!Also anguish is in the whole bodyAnd all their faces are grown pale!