Genesis 24:2

Servant. Eliezer, or Damascus, whom he had once intended for his heir, chap. xv. 2. (Haydock) --- Under, &c. either to shew their subjection, (Sa.) or their faith in Christ, who should be born of Abraham, (St. Jerome, ep. 140) or to testify that their oath shall be no less binding than the covenant of circumcision. For this last reason, the Jews still observe the custom of sitting upon the hand of the person who takes an oath. (Menochius) See chap. xlvii. 29, where Jacob imitates the action of his grand-father. These two patriarchs, progenitors of Christ are the only ones in Scripture whom we find practising it; whence St. Augustine and St. Ambrose conclude, that it had a reference to the mysterious birth or our Redeemer. (Bonfrere.)