Well, for us to know the truth about the mystery of God (I Tim. 3:16), let's not forget what is written on the Bible that God IS ONLY ONE (Isa. 43:10-11, 44:8, 45:5, 21, 46:9). In Philippians 2:6-8 says that God humbled himself and take the form of man. Who was He?? Of course, our Lord Jesus Christ! who was born under the law (Gal. 4:4).. and One of the great laws of God is to "love God above all things for He is a jealous God" (Deut 20:3-5). Since, Lord Jesus Christ was in the form of men while on earth, He gave respect and honor to the throne He left in Heaven (God the Father), which is also another example He left for us (humans) to give glory to God just what He did when He was in the flesh. So, let us not confused ourselves why He's calling God the Father (His position before He left His throne in heaven) because during His time on earth, He was just a man (like us) and was even called the Son of God. But these titles are only applicable to Him during His time on earth, when He ascended to heaven, He returned to His original position which God the Father (John 16:28). If we consider God the Son and God the Father as two beings then we became liars for what is written "there's ONLY ONE God in Heaven."
Actually, there's a perfect example written in the Bible, one of the disciples who wants to see the Father that our Lord Jesus Christ was always talking about. Please read on John 14:8-9, Philip said, "Lord, show us the Father and that will be enough for us." But Jesus answered: "Don't you know me, Philip, even after I have been among you such a long time? Anyone who has seen me has seen the Father. How can you say, 'Show us the Father'?" We can see clearly see here and understand that Jesus Christ is the Father for if not, He would't say the last line "How can you say, 'Show us the Father!" (meaning it's impossible what Philip is asking for) but instead He might reply like this.. "Philip, it's true that I have Father in heaven but you just wait a little while and soon you'll meet Him".
After reading this and still you don't understand, I urge you to pray to God and ask the knowledge and wisdom which He gives generously to all without finding fault. (James 1:5). God bless...