"We are informed that there are many earths or worlds which have been created, and were created by the Son for the Father. This was, of course, before he was born a Babe in Bethlehem.

Evidently his Father passed through a period of mortality even as he passed through mortality, and as we all are doing. Our Father in heaven, according to the Prophet, had a Father, and since there has been a condition of this kind through all eternity, each Father had a Father, until we come to a stop where we cannot go further, because of our limited capacity to understand."

(Joseph Fielding Smith, Doctrines of Salvation, 3 vols., edited by Bruce R. McConkie [Salt Lake City: Bookcraft, 1954-1956], 2: 47.)