Yet there are some passages of Scripture that might at first glance seem to deny any plurality in the Godhead. Unitarians latch onto such verses to argue that Jesus cannot be God along with the Father while many Trinitarians use such verses to deny man's destiny of becoming part of the God family.

In Deuteronomy 32:39 Deuteronomy 32:39See now that I, even I, am he, and there is no god with me: I kill, and I make alive; I wound, and I heal: neither is there any that can deliver out of my hand.
American King James Version×God states, "Now see that I, even I, am He, and there is no God besides Me." In Isaiah 45:5 Isaiah 45:5I am the LORD, and there is none else, there is no God beside me: I girded you, though you have not known me:
American King James Version×He says, "I am the Lord, and there is no other; there is no God besides Me." And Isaiah 44:6 Isaiah 44:6Thus said the LORD the King of Israel, and his redeemer the LORD of hosts; I am the first, and I am the last; and beside me there is no God.
American King James Version×tells us, "Thus says the Lord, the King of Israel, and his Redeemer, the Lord of hosts: 'I am the First and I am the Last; besides Me there is no God.'"

So can the Father and Christ both be God in light of these verses? Yes, They can. According to several passages in the New Testament, the One who spoke these words was the One who became Jesus Christ. Indeed, Jesus refers to Himself as the First and the Last in the book of Revelation (Revelation 1:11 Revelation 1:11Saying, I am Alpha and Omega, the first and the last: and, What you see, write in a book, and send it to the seven churches which are in Asia; to Ephesus, and to Smyrna, and to Pergamos, and to Thyatira, and to Sardis, and to Philadelphia, and to Laodicea.
American King James Version×; Revelation 17:1-18 Revelation 17:1-18 [1] And there came one of the seven angels which had the seven vials, and talked with me, saying to me, Come here; I will show to you the judgment of the great whore that sits on many waters: [2] With whom the kings of the earth have committed fornication, and the inhabitants of the earth have been made drunk with the wine of her fornication. [3] So he carried me away in the spirit into the wilderness: and I saw a woman sit on a scarlet colored beast, full of names of blasphemy, having seven heads and ten horns. [4] And the woman was arrayed in purple and scarlet color, and decked with gold and precious stones and pearls, having a golden cup in her hand full of abominations and filthiness of her fornication: [5] And on her forehead was a name written, MYSTERY, BABYLON THE GREAT, THE MOTHER OF HARLOTS AND ABOMINATIONS OF THE EARTH. [6] And I saw the woman drunken with the blood of the saints, and with the blood of the martyrs of Jesus: and when I saw her, I wondered with great admiration. [7] And the angel said to me, Why did you marvel? I will tell you the mystery of the woman, and of the beast that carries her, which has the seven heads and ten horns. [8] The beast that you saw was, and is not; and shall ascend out of the bottomless pit, and go into perdition: and they that dwell on the earth shall wonder, whose names were not written in the book of life from the foundation of the world, when they behold the beast that was, and is not, and yet is. [9] And here is the mind which has wisdom. The seven heads are seven mountains, on which the woman sits. [10] And there are seven kings: five are fallen, and one is, and the other is not yet come; and when he comes, he must continue a short space. [11] And the beast that was, and is not, even he is the eighth, and is of the seven, and goes into perdition. [12] And the ten horns which you saw are ten kings, which have received no kingdom as yet; but receive power as kings one hour with the beast. [13] These have one mind, and shall give their power and strength to the beast. [14] These shall make war with the Lamb, and the Lamb shall overcome them: for he is Lord of lords, and King of kings: and they that are with him are called, and chosen, and faithful. [15] And he said to me, The waters which you saw, where the whore sits, are peoples, and multitudes, and nations, and tongues. [16] And the ten horns which you saw on the beast, these shall hate the whore, and shall make her desolate and naked, and shall eat her flesh, and burn her with fire. [17] For God has put in their hearts to fulfill his will, and to agree, and give their kingdom to the beast, until the words of God shall be fulfilled. [18] And the woman which you saw is that great city, which reigns over the kings of the earth.
American King James Version×; Revelation 2:8 Revelation 2:8And to the angel of the church in Smyrna write; These things said the first and the last, which was dead, and is alive;
American King James Version×; Revelation 22:13 Revelation 22:13I am Alpha and Omega, the beginning and the end, the first and the last.
American King James Version×). Yet wouldn't the Father, then, be another God besides Him? No—the Father is not another God. Rather, the Father and Jesus Christ are both God. But how so?

Trinitarians would argue that this is because the Father, Son and Holy Spirit are one triune being. But the true explanation is that the one God is the one God family. In fact, the Hebrew word for "God" in these verses is the plural Elohim (see "Elohim: The Plurality of God"). Yet so unified is the family that Christ as divine Spokesman speaks with singular voice on the Father's behalf.

The real message in these pronouncements is that there is no other God apart from the true God—that is, outside the God family now consisting of two divine Beings, the Father and the Son. In short, the God family alone is God. This even allows for the addition of others to the divine family—a truth spelled out in Scripture, as explained in this chapter.

But what of the following verses? In Isaiah 42:8 Isaiah 42:8I am the LORD: that is my name: and my glory will I not give to another, neither my praise to graven images.
American King James Version×God says, "I am the Lord, that is My name; and My glory I will not give to another, nor My praise to carved images." Does that mean human beings cannot receive divine glory? Other passages reveal that God will indeed share His divine glory with His children who are transformed into His image. What, then, is meant here? Note that in parallel, God will not share praise with idols. We should understand His not sharing glory in the same way. God will not share divine glory with any false gods. Rather, the true God's glory is reserved exclusively for the true God—but, again, the true God means the one God family to which others will yet be added. 

And lastly, God states in Isaiah 43:10 Isaiah 43:10You are my witnesses, said the LORD, and my servant whom I have chosen: that you may know and believe me, and understand that I am he: before me there was no God formed, neither shall there be after me.
American King James Version×, "Before Me there was no God formed, nor shall there be after Me." Again, the word "God" here is translated from the plural Elohim. And of courseno God could be formed before or after God—for there is no such time as before or after God, who is eternal. The point here is that God has always been God and always will be. He will never be replaced. And those who are added to the family are not separately formed gods but, rather, spring from the Father's very being as His own children—becoming part of the one God family with the Father and Christ.

Thus, none of these verses contradict the biblical truth that God is a family—presently with two divine members, the Father and Jesus Christ, and multitudes more yet to be added.