Adam Clarke on Job 15:19

Unto whom alone the earth was given - He very likely refers to the Israelites, who got possession of the promised land from God himself; no stranger being permitted to dwell in it, as the old inhabitants were to be exterminated. Some think that Noah and his sons may be intended; as it is certain that the whole earth was given to them, when there were no strangers - no other family of mankind - in being. But, system apart, the words seem to apply more clearly to the Israelites.