I appeared... by the name of God Almighty. — This name, “El Shaddai,” is first found in the revelation made of Himself by God to Abraham (Genesis 17:1). It is used by Isaac (Genesis 28:3), and repeated in the revelation made to Jacob (Genesis 35:11). Its primary idea is, no doubt, that of “overpowering strength.” (See the comment on Genesis 17:1.) The primary idea of “Jehovah” is, on the contrary, that of absolute, eternal, unconditional, independent existence. Both names were probably of a great antiquity, and widely spread among Semitic races; but, at different times and in different places, special stress was laid on the one or on the other. To the early patriarchs God revealed Himself as “El Shaddai,” because He desired to impress upon them His ability to fulfil the promises which He had made to them; to Moses and Israel generally, at the date of the Exodus, He insisted on His name Jehovah, because they were in the closest contact with polytheism, and had themselves, in many cases, fallen into polytheism (Joshua 24:14), against which this Name was a standing protest, since “the Existent” must mean “the Self Existent,” and so “the Only Existent.” (See Deuteronomy 4:39 : “Jehovah, he is God in heaven above, and upon the earth beneath: there is none else”)
By my name Jehovah was I not known to them. — Rather, was I not made manifest to them. The antiquity of the name itself appears — (1) from its derivation, which is from the obsolete havah, a form already in the time of Moses superseded by hayah; (2) from its occurrence in some of the most ancient documents inserted by Moses into the Book of Genesis, e.g., Exodus 2:4; Exodus 2:3-4; Exodus 11:1-9, &c.; (3) from its employment by Abraham as an element in a name (Genesis 22:14). But though the name was ancient, and known to the patriarchs, its full meaning was not known to them, and so God was not manifested to them by it.