Who or what is God?
"God is Spirit.." (John 4:24) and "...a spirit does not have flesh and blood." (Luke 24:39)
The Bible tells us that God has revealed himself to man through the prophets:
"God, who at various times and in various ways spoke in time past to the fathers by the prophets" (Hebrews 1:1).
The writings of the prophets became the Holy Bible:
"All Scripture is given by inspiration of God, and is profitable for doctrine..." (2 Timothy 3:16).
The final revelation of God came through his Son, Jesus:
"No one has seen God at any time. The only begotten Son, who is in the bosom of the Father, He has declared Him." (John 1:18)
Jesus said "I and My Father are one." (John 10:31). When God spoke to Moses, Moses asked God ...
... for his name. "And God said to Moses, "I AM WHO I AM." And He said, "Thus you shall say to the children of Israel, 'I AM has sent me to you.'" (Exodus 3:14)
When the Jewish leaders were questioning Jesus about his identity, he responded by saying, "Most assuredly, I say to you, before Abraham was, I AM." (John 8:58) Jesus declared himself to be God. He was either God, a liar or a lunatic. You do not call someone who called himself God a good teacher unless he truly was God. If you consider Jesus only a good teacher, and do not believe He is God, you are calling him a liar or a lunatic. You cannot have it both ways.
The word "Trinity" is not found in the Bible. Yet the Bible declares this doctrine. First, God is revealed as being one God:
"Hear, O Israel: The Lord our God, the Lord is one! (Deuteronomy 6:4)
with three distinct persons:
"...baptizing them in the name of the Father and of the Son and of the Holy Spirit" (Matthew 28:19)
"..elect according to the foreknowledge of God the Father, in sanctification of the Spirit, for obedience and sprinkling of the blood of Jesus Christ..." (1 Peter 1:2)
Because of this, we can have assurance of salvation. If Jesus is not God, then his death on the cross could not pay the price for all men's sins. If Jesus and the Father are not both God yet distinct persons, how could Jesus pray to God while He was here on earth? If the Holy Spirit is not God, then how could we grieve Him (4:30), lie to Him (Acts 5:3) or blaspheme Him (Matthew 12:32, Mark 3:29, Luke 12:10)?
There are many gods that people worship. If your god is not the God of the Bible, revealed as the Father, Son and Holy Spirit, you worship a false god. Listen to what Jeremiah said in Jeremaih 10:
"But the Lord is the true God; He is the living God and the everlasting King." (Jeremiah 10:10)
Who is the true God? Compare 1 John:
"And we know that the Son of God has come and has given us an understanding, that we may know Him who is true; and we are in Him who is true, in His Son Jesus Christ. This is the true God and eternal life." (1 John 5:20)
If Jesus is not your God, then you do not know God. He wants to know you.
"Be still, and know that I am God; I will be exalted among the nations, I will be exalted in the earth! (Psalm 46:10)