Jesus is the Eternal Word, the Eternal Logos, who is eternally begotten of the Father and equal to the Father. When he became incarnate by the Holy Spirit in the womb of his blessed Mother, he took on a human nature and entered time. His human nature had a beginning. We don’t want to create a problem where there is none. The fact that Jesus took on a human nature in no way diminishes the Holy Trinity. One of the Persons of the Holy Trinity, since the Incarnation, simply has a human nature as well as a divine one. If we said that his human nature supplanted his divine nature, we would have a problem. But such is not the case and could never be.