Give a simple explanation of the Trinity.

Very simple from a old country preacher.

3 separate candles burning, put the 3 candles together and they become 1 flame, pull them apart and there are still 3 candles burning.

In the beginning was the 2>Word, and the Word was 1>with God, and 2>the Word was God.

3> And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth. 15John bare witness of him,...

I think John's got the answer covered... and his view would explain why Jesus was with the Father in the beginning.

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So in the beginning was the Word and God . They were two but were also one and the same as John explains. And then the Word and Jesus are two and one or the same as John explains again, only we know by now that the Word is also two both God and the Word, therefore Jesus is God: Jesus being the Word made flesh.

So the trinity comes to us from John's view of God as being Jesus the Word (God) made flesh and this>>>>

( John 14:16 And I will ask the Father, and he will give you another advocate to help you and be with you forever--)