The “Trinity” can not be explained fully; but I will try to explain it, albeit feebly, since so many misconceptions exist. Some of the backlash is due to the word, itself, not appearing with in Scriptures. This Glorious concept of The One God is not three gods.
It will be better to define this concept as a “tri-unity” or “Tri-Une”, which does exist within many Scriptures, including the Qur’an. Implied, would be God using plural terms for Himself, such as: “We, Our, Us” or “Elohim”; yet He is The (singular) God.
The concept is more than just implication, elsewhere. For example, in Isaiah 63, alone, exists the “tri-unity” concept thrice: I will paraphrase from the TANAKH (of the wine press scene of the End Day “My year of redemption arrived. There was none there to help, so My own Arm worked the triumph”). 8-10: “Surely they are My people, children who will not play false. So He was their Deliverer. In all their troubles He was troubled. And the angel of His Presence delivered them. In His Love and Pity. He Himself Redeemed them, Raised them and exalted them all the days of old. But they rebelled and grieved His Holy Spirit.” 11-12: “Where is He who put in their midst His Holy Spirit, Who made His glorious Arm…” 14: “Twas the Spirit of the LORD gave them rest…” 16: Surely you are our Father: though Abraham regard us not, And Israel recognize us not, You O LORD, are our Father; from of old Your name is ‘Our Redeemer'” (Isaiah 63:8-10; 11-12; 14-16).
The Creator is above all since He created all things; and it was His “Spirit (that) moved upon the waters” (Gen. 1:1). God does not “have” a spirit (or He’d be human). He “IS” Spirit. Invisible. God is Holy of all holy; and therefore the One and only Holy Spirit.
God created Adam and then God’s Holy Spirit (Ruach) breathed life into him (Gen. 2:7). Conversely, God “breathed” His Spirit into the virgin Mary and created Jesus Christ (Messiah).
Jesus was similar to Adam, but unique: God’s Holy Spirit walked in flesh. This made him the “Son of God”, whom he called “Father” or our “Father”; but the Father is not a father (as man thinks of one). Heaven forbid! God’s Holy Spirit created His Only Son, Jesus Christ, and he lived a holy life.
Jesus most often referred to himself as the “Son of Man”, but his relationship to Almighty God, Creator of Heaven and Earth, was so “One with God” that he spoke “only what I hear God say”; and he foretold his mission: “I choose to lay down my life for all of you who believe.” (i.e. the Jews and Romans didn’t kill him, per se). Afterwards, he arose on the third day, and so his body did not see decay: God took him, as prophecy foretold!
Jesus now at the Right Hand of God; his “Arm”. Our friend, Jesus, advocates for believers, as he had for Job of the TANAKH, who testified: “Even now my witness is in heaven: my advocate is on high. My intercessor is my friend as my eyes pour out tears to God: on behalf of a man he pleads with God as a man pleads for a friend” (16:19-21).
Jesus prophecized, but is unlike any other who prophecized. The Prophets and faith-filled followers testify “he was there in the beginning” and will be there in the End”; he is the “Alpha and Omega” who “was and will be” (but we also know “he is”). John 1:1-18; Revelation 22:12-16; Gen. 1:26; Proverbs 8:22-23; 30-36; Proverbs 30:2-4).
The Messiah was, is, and will be–the exact meaning of יהוה “LORD”, the “I AM” revealing himself to the faith-led of the “first Testament”. This (the Old Testament) is “prophecy foretold” & prepared the way for the “prophecy revealed” (the Evangel) and “the prophecy retold” (the Qur’an).
Within each writing are fulfilled prophecies. About one third remain to be fulfilled. These are the last prophecies concerning the End of Days. Jesus said “you will see (me) the Son of Man descending on the clouds”; “no one but the Father knows when, not even the Angels nor the Son (referring to himself).”
Jesus said, “a word spoken against the Son of Man will be forgiven, but blasphemy against the Holy Spirit will not be forgiven; neither in this world or the next”. Know ye the truth of this tri-unity of ONE.
The Holy Spirit of God fully tabernacled within Jesus Christ, the Messiah. Meanwhile, the prophets and his followers embody only some of this Holy Spirit.
Remain in Him so that you, mere strangers who are tabernacled in a world filled with evil, will overcome. Learn, and be filled with the Holy Spirit, which will make right-living and worship “in the Spirit” easier.
God is One, with distinctive attributes of Tri-Unity.