So for all of you who claim GOD is Jesus and Jesus is GOD - whose voice was this coming from the cloud:
Matthew 17:5 King James Version (KJV)
5 'While he yet spake, behold, a bright cloud overshadowed them: and behold a voice out of the cloud, which said, This is my beloved Son, in whom I am well pleased; hear ye him.'
Was Jesus a ventriloquist? Can clouds speak? Maybe this verse is fiction like most non-Christians believe?
If you want to know the meaning of what Jesus meant in Matthew 3:15, it was to fulfill the prophesy of Isaiah in 48:16-17 testifying to the Three Witnesses within the One God that the God the Father & the Holy Spirit sent God Our Redeemer.
Matthew 3:5 And Jesus answering said unto him,
Suffer it to be so now: for thus it becometh us to fulfil all righteousness. Then he suffered him. 16 And Jesus, when he was baptized, went up straightway out of the water: and, lo, the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him: 17 And lo a voice from heaven, saying, This is my beloved Son, in whom I am well pleased.
Isaiah 48:16 Come ye near unto me, hear ye this; I have not spoken in secret from the beginning; from the time that it was, there am I: and now the Lord God, and his Spirit, hath sent me. 17 Thus saith the Lord, thy Redeemer, the Holy One of Israel; I am the Lord thy God which teacheth thee to profit, which leadeth thee by the way that thou shouldest go.
There are 3 Persons/Witnesses within the One God for how God establish a word in creation and to judge anyone by. If you see what God commands of men to have 2 or 3 witnesses to establish a testimony or to judge any one, that testifies to the Three Witnesses within the One God.
Deuteronomy 17:6 At the mouth of two witnesses, or three witnesses, shall he that is worthy of death be put to death; but at the mouth of one witness he shall not be put to death.
Deuteronomy 19:15 One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.
So if you consider why the Father spoke from Heaven and requires Another Witness for His witness of the Son from heaven to be true, look at what God commands of men here again.
John 8:17 It is also written in your law, that the testimony of two men is true.
Then you can see why the Holy Spirit descended from Heaven to alight on the Son to add Another Witness to what the Father said as being true and fulfilling the prophesy of Isaiah 48:16-17 as the Lord God and His Spirit sent Him, God Our Redeemer.