The word Trinity is not mentioned in the Bible, but scripture is all about the Trinity! Christianity is monotheistic, but yet we acknowledge three aspects of God. (I didn't use "persons" because that word is reserved for individuals. God is NOT an individual with personhood. He doesn't even have personality because he is not a person!) God just IS and his name is just that. In the first person present tense God just says that he is "I AM".
Monotheism is the worship of one God. JHVH (I AM THAT I AM) is the One True God. That's important because God is the Creator of all. The aspects of the Holy Trinity were God's characteristics in the beginning. There were not three persons, but three relationships with mankind. Hence, the Holy Trinity are aspects which describe mankind's relationships to God.
The trinity is any grouping of three things. Fire, water and air are a trinity occurring in nature. The Holy Trinity is a grouping of three with respect to the divine. The Holy Trinity is not made up of things, nor persons, so therefore three aspects. In this case "aspects" are ways of looking at the same thing. For the divine, the Holy Trinity is looking at God from three different viewpoints. Those aspects are God's nature, albeit God is not natural, but supra-natural!
Because God is divine even finding terms to define him are futile because God isn't common; God is Glory, and glory is the essence of God. Then what is glory? It's God's presence. It's a perfect existence. It will be our existence when we die and move from the natural to glorious as we are changed in the presence of God from natural to supra-natural. That's when we become Supra-people because even gender will be of no consequence without the need for procreation! However, until we become Supermen or Supergirls, we are natural men or natural girls, but even though we're not divine, we have a trinity within us, and it's a poor copy of the Holy Trinity.
In the beginning there was God the Father, his Holy Spirit and the Word who later became flesh (John 1). References to the Holy Trinity are many in scripture, but the most direct is:
Matthew 28:19 ( ESV) "Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit..."Elsewhere we find that the aspects of the Trinity complement each and are together God who has three forms: Creator (Father), Jesus (his Son) and the Holy Spirit (the atmosphere, magnificence or glory of God), and all are God. The form of the three are as follows: Creator (Power; Almighty God), Jesus (God in the flesh) and Spirit (the essence or breath of God which flows from him). The specific Spirit that resided in Jesus on the cross and suffered with him as he died was, I believe, the ghost of Jesus, called the Holy Ghost. That portion was specific to Jesus and became general to Christians, and is Jesus who resides within us when we are born-again.
Now, that mention brings up our trinity, which is not divinity. We were made in the image of God! What was God's image: Creator, Jesus, and the Holy Spirit. (Yes, Jesus is God with us!)
Our trinity is mind, body and soul. As such they are the natural renditions of the supra-natural Holy Trinity: mind is the Father Creator with supreme knowledge who makes thing happen by the power of his will, body is God incarnate: Jesus Christ, and soul is the container for the Holy Spirit which I believe is the "cup" of which Jesus spoke. Since these are mere images of God as the Word told us, they are not divine; we just try to make them so!
Mankind's problem is the same as Adam's: 'You shall be as gods," Satan told them. Adam ate and his trinity became the Natural Trinity because he was no longer in the image of God, but assumed God's authority by rebellion. Ever since men have worshiped their own selves besides God, with the sub-conscious desire to circumvent God by doing what is right in our own eyes!
Not only do we have a natural trinity patterned after God's Holy Trinity, but the nether world has their Unholy Trinity: Satan, the Anti-Christ and the False Prophet. Sinful man is more like the Unholy Trinity than the Holy Trinity: we are trinity, but we're not divinity!
Satan rules the sinful man's mind, the Anti-Christ is Satan in the flesh and the False Prophet is the Unholy Spirit who discomfits men! Our divine God is the Holy Trinity who adopts us because we once were his heirs, but the evil God-pretender is the Unholy Trinity who kidnapped mankind and replaced the holy with the unholy! Satan is sinful man's mind, the Anti-Christ is sinful man's body or presence, and the False Prophet is following unholy lies. Unless we are born-again as sons of God, our nature is as the composite of the Unholy Trinity.
Now you know: You are trinity, but not divinity, but act as if you are God! That acting is the re-creation in the image of Satan.