Verses with the word asleep in the Old Testament (4 verses):

Judges 4:21
Then Jael Heber's wife took a nail of the tent, and took an hammer in her hand, and went softly unto him, and smote the nail into his temples, and fastened it into the ground: for he was fast asleep and weary. So he died.

1 Samuel 26:12
So David took the spear and the cruse of water from Saul's bolster; and they gat them away, and no man saw it, nor knew it, neither awaked: for they were all asleep; because a deep sleep from the LORD was fallen upon them.

Canticles 7:9
And the roof of thy mouth like the best wine for my beloved, that goeth down sweetly, causing the lips of those that are asleep to speak.

Jonah 1:5
Then the mariners were afraid, and cried every man unto his god, and cast forth the wares that were in the ship into the sea, to lighten it of them. But Jonah was gone down into the sides of the ship; and he lay, and was fast asleep.