To Oneness Pentecostals the sonship began at the birth of Jesus. This is what was called adoptionism which had this occur at birth or at the baptism.

What exactly is meant by literally conceived is not explained and is left up to ones imagination.

I find the most illogical flaw they present is that the Father became his own Son, that the H.Spirit is the begetter and that deity has an offspring of flesh. Is this really a literal presentation or an interpolation. God uses human terminology to communicate to man eternal qualities which cannot be taken in a solid literal sense. For an example Christ is referred to as a hen and even a lion, does this mean he actually roars and eats raw meat? The devil is also identified as a lion does this mean he and Christ are the same being ? No of course not, and neither should we take begotten in the human understanding of the word. Begotten doesn’t mean offspring anymore than the word firstborn means Christ is the firstborn in a family ? If you ask a Jehovah Witness you might get that kind of an answer. There are numerous example used to prove how this word is used. In Jer. 31:9 "For I am a Father to Israel, and Ephraim is my firstborn." God calls Ephraim the Son of Joseph his first born yet Ephraim was Joseph’s second Son born after Mannaseh. The obvious shows that the term firstborn means something other than the first offspring.

God asked Abraham to take his only Son Isaac to the Altar on Mt. Moriah yet we know he had Ishmael as his firstborn son. Even in Ex.4:22 Israel is called Gods firstborn Son. No one would consider God actually begot a nation in a literal sense as we do people ! Both Col.1:15 and Rev.1:5 both clarify the meaning of firstborn to mean risen from the dead eternally. The Greek word Prototokos is found 9 times in the N.T. It means first in rank, a heir, to have preeminence. The historical context clarifies this conclusion as well. There is a strong association of the firstborn child with preeminence and inheritance in Hebrew culture (W.E. Vine, Merril Unger, Wm. Whice, Jr., eds., Vine's Expository Dictionary of Biblical Words, p. 240-1)." (p.98). One does not have to look far to see the apple does not fall far from ones own tree. The word they use to describe God as Oneness is not found either with a host of other words following. This is not to discourage using terms not found in the scriptures to define meanings. But these kind of fallacious arguments should be kept in the refrigerator on ice and not thawed out.

If God calls him his Son and calls the Son God, what does that make him ? The Son of God. That was easy now lets prove it. Heb. 1:8 God the Father says to the Son ‘your throne O’ God is forever and ever".

vs.10 the Father still speaking to the Son "and you, Lord, in the beginning laid the foundation of the Earth and the heavens are the work of your hands..." Who are we going to believe the Oneness reasoning or Gods clear proclamation.

According to the scriptures Christ did not become the Son by either his birth or adoption. but was eternally the Son.

Ps.2:7" I will declare the decree: the LORD hath said unto me, Thou art my Son; this day have I begotten thee." The word for today is referring to time, but is used as a timeless today, it is in the eternal present, which knows no past or future. Jesus did not become the son by adoption this is a timeless declaration of him being the Son from all eternity.

There are several times Jesus is called the Son by the Father in a audible voice. He did not become the Son each time he was called. For one to call another his Son Identifies him as his Father. Both needing to be different in identity.

At the baptism Mt.3:17 a voice from heaven speaks This is my beloved Son, in whom I am well pleased.

At the transfiguaration (in Mt. 17:5, Mk.9:7. Luke 9:35) After the disciples see his glory of who he really is a voice from heaven speaks that this is his beloved son hear him. Notice he does not say hear me (the Father). Is God pointing to a human, no he's pointing to his Son, as deity.

After the resurrection Paul applies Acts 13:33" God hath fulfilled the same unto us their children, in that he hath raised up Jesus again; as it is also written in the second psalm, 'Thou art my Son, this day have I begotten thee." Are we to think that the Son was literally begotten after he rose ? This declares the fact of what the Father spoke that the Son is indeed Lord. He is the firstborn from the dead.

Rom.1:3 "...and declared the Son of God with power according to the Spirit of holiness, by the resurrection of the dead. Did Jesus become the Son by the resurrection? No he already was the Son. The Father proclaimed to all people for all time that Christ was his Son by the fact of the resurrection.  He being the only man raised in a body unto eternal life.

Heb.1:5 " For unto which of the angels said he at any time, Thou art my Son, this day have I begotten thee? And again, I will be to him a Father, and he shall be to me a Son? These events all share in common that it was a decree announcing publicly who he is openly declaring him to be the son of God. Each time was a specific revelation to certain people.