Genesis 15:2

I shall go. To what purpose should I heap up riches, since I have no son to inherit them? Abram knew that God had promised him a numerous posterity; but he was not apprized how this was to be verified, and whether he was to adopt some other for his son and heir. Therefore, he asks modestly, how he out to understand the promise. --- And the son, &c. Hebrew is differently rendered, "and the steward of my house, this Eliezer of Damascus." We know not whether Eliezer or Damascus be the proper name. The Septuagint have "the son of Mesech, my handmaid, this Eliezer of Damascus." Most people suppose, that Damascus was the son of Eliezer, the steward. The sentence is left unfinished, and must be supplied from the following verse, shall be my heir. The son of the steward, filius procurationis, may mean the steward himself, as the son of perdition denotes the person lost. (Calmet)