"you are from below, I am from above. You are of this world; I am not of this world. I told you that you would die in your sins; if you do not believe that I am the one I claim to be (ESV) | I am He (NIV, KJV), you will indeed die in your sins. " Jesus said in John 8: 23 - 24. (ESV)
Here, Yehoshua spoke clearly that he is G-d the Father himself. As he referred himself to He, there is no one beside his Father. He and His Father are one from the beginning.
when Jehovah Witnesses denied that Yehoshua is G-d himself, they will die in their sins according to what the Lord says. which death does Yehoshua speak of? As the Son of G-d is of the True Spirit, he would not speak of the physical death, but the spiritual death, the second death of human souls. To strength this point, the Bible also says that every one dies, and there is a Judgement after death. Yehoshua could not speak of the physical death as every single human dies save only two men in the entire history die not. They are Enoch and Elijah.
Therefore, it is the second death that the Lord comes to save us because without his salvation, all souls will die after the judgement. For none of these unsaved souls will live the second life. Who will have this second life? All those who believe in Jesus Christ and have and obey his commandments and teachings.
Regarding all Muslims, they deny G-d the Father can have a son. It is funny as they all proclaim that the Almighty G-d can do whatever he wants while, they deny that he can have a son. It is a ridiculous statement from many Muslims. Further more, they deny that Yehoshua can save human beings as only G-d can do so. By their belief, they have denied that Yehoshua is G-d himself. Because from the Beginning, G-d is one and only. Yehoshua was with G-d and was his Word and his Voice, his Power. It is a mystery that how part of G-d became a flesh. but yet, it is truly recorded in the Bible that everything created in heaven and on this earth and within the earth were by Yehoshua, through Yehoshua. Nothing was created without Him. Praise from all the earth and the heavens be to Him and His awesome Name. Amen.
Therefore, by trusting the words of our Lord and Savior Yehoshua, we firmly believe that He is G-d himself. He and the Father are one. Amen.