Genesis 8:7

And he sent forth a raven, which went forth to and fro, until the waters were dried up from off the earth.

Sent forth a raven - literally, the raven. The article has here the force of a certain, a particular raven (cf. Genesis 28:17; 1 Samuel 17:34; 1 Kings 20:36; Isaiah 7:14). It is a bold and adventurous bird, hardy, and unaffected by the coldest atmosphere, delighting to wade in mud and to feed on the carcasses of animals.

Which went forth to and fro - literally, went forth going and returning; i:e., roving on the heights that had emerged from the waters, or perched on the external covering of the ark, so that he was at no loss for a resting-place, and his voracious appetite would find plenty of carrion floating on the slimy hillsides on which, after so long an abstinence, he would greedily prey.