Genesis 15:2-4

Young's Literal Translation

² And Abram saith, `Lord Jehovah, what dost Thou give to me, and I am going childless? and an acquired son in my house is Demmesek Eliezer.'

³ And Abram saith, `Lo, to me Thou hast not given seed, and lo, a domestic doth heir me.'

⁴ And lo, the word of Jehovah [is] unto him, saying, `This [one] doth not heir thee; but he who cometh out from thy bowels, he doth heir thee;'