Semi-modalism is a false doctrine which teaches that God is a person who is three persons, the Father, the Son, and the Holy Spirit. This belief is as unbiblical as it is absurd; for a general treatment of it see Modalism has evolved and Semi-modalism and the Introduction of a Four-Person Trinity.
A very common line of thinking for semi-modalists and those deceived by them makes an attempt to present a biblical case for the doctrine, which runs as follows: The LORD is the God of the Bible, the one and only God; The Father, Son, and Holy Spirit, are all each called by the name “LORD”; therefore, the Father, Son, and Holy Spirit are together all really the one person named ‘LORD’, Who is simultaneously the Father, the Son, and the Holy Spirit.
This simple syllogism seems at first glance to present a genuinely biblical case for semi-modalism; but the argument breaks down when we examine it in detail. A major assumption of the argument is that there is ultimately only one person called by the name ‘LORD’; this assumption is easily shown false. The scriptures use the name ‘LORD’ for multiple distinct persons without ever indicating that this is meant to indicate that They are collectively a single person; in fact to draw such a conclusion is to import one’s own idea into scripture without any warrant from the text.
Rather than teaching that the Father and Son are called by the same name ‘LORD’ because They are somehow together a single person, scripture explains this sharing of God’s name with His Son in the following terms:
“I am no longer in the world; and yet they themselves are in the world, and I come to You. Holy Father, keep them in Your name, the name which You have given Me, that they may be one even as We are.” (John 17:11 NAS)
“While I was with them, I was keeping them in Your name which You have given Me; and I guarded them and not one of them perished but the son of perdition, so that the Scripture would be fulfilled.” (John 17:12 NAS)
“For this reason also, God highly exalted Him, and bestowed on Him the name which is above every name,” (Philippians 2:9 NAS)
“[the Son] having become as much better than the angels, as He has inherited a more excellent name than they.” (Hebrews 1:4 NAS)
These passages of scripture clearly teach that the Father, Who scripture alone calls the “one God”, gave the Son His own name. This is not the name “Father”, but the name which is described as being “above every name”. Those even a little familiar with the supreme glory ascribed to the Covenant name of God, “LORD”, in the Old Testament scriptures should be able to instantly know which name this refers to. The name “LORD” is this name the Son was given by the Father, to which every knee shall bow.
It is fitting that the Son should share in the glory of the Father’s name, when we consider His identity as His eternal Son, Who eternally reflects His glory in His own distinct person.
For this reason, we not only see the New Testament apply Old Testament verses that refer to a person named “LORD” in reference to the Son, but even throughout the Old Testament we can clearly see the pre-incarnate Son called by this name; repeatedly the Angel of the LORD is called “LORD” Himself, even while He is clearly distinguished from the LORD in heaven, whose Messenger (or Angel; the Hebrew word is the same for both) He is. Thus as the church fathers pointed out, we read in Genesis 19:24 that “Then the LORD rained on Sodom and Gomorrah brimstone and fire from the LORD out of heaven,” (NAS); we clearly see the distinct persons of both the Father and the Son being called by the same name “LORD”.
The syllogism employed by the semi-modalists is shown false then, on the grounds of its faulty assumption that the name “LORD” belongs to one person only. For although it belongs properly to the Father, the one God, as His own name, scripture reveals to us that He has bestowed this same glorious name on His own only-begotten Son as well.