The study of the Trinity is a great and complicated one. So do not be distressed by having difficulty in understanding the subject. “Trinity” is a theological term (not found in the Bible) which is used in Systematic Theology to express the concept of the Triune God: one God, in three Persons, as revealed throughout the Bible. Here are a few examples:
And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the birds of the heavens, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.
(Genesis 1:26 ASV)
In the beginning was the Word, and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made through him; and without him was not anything made that hath been made. In him was life; and the life was the light of men.
(John 1:1-4 ASV)
The Great Commission
And Jesus came to them and spake unto them, saying, All authority hath been given unto me in heaven and on earth. Go ye therefore, and make disciples of all the nations, baptizing them into the name of the Father and of the Son and of the Holy Spirit: teaching them to observe all things whatsoever I commanded you: and lo, I am with you always, even unto the end of the world.
(Matthew 28:18-20 ASV)
(Scofield Reference Notes, The Scofield Bible, copywright 1917)
The word is in the singular, the “name,” not names. Father, Son, and Holy Spirit is the final name of the one true God. It affirms:
(1) That God is one.
(2) That He subsists in a personality which is threefold,
b. indicated by relationship as Father and Son;
c. by a mode of being as Spirit;
d. by the different parts taken by the Godhead in manifestation and in the work of redemption,
for example (John_3:5-6); (Spirit), (John_3:16-17) (Father and Son). In; (Mat_3:16-17); (Mark_1:10-11); (Luke_3:21-22); the three persons are in manifestation together.
(3) The conjunction in one name of the Three affirms equality and oneness of substance.
For a deeper study, this site may be of help in trying to understand the theology of the Trinity:
“The Father, the Son, and the Holy Spirit are revealed as concurring together in the whole purpose and plan of man’s redemption; but as sustaining, each of them, a distinct office, and undertaking a different part of the work, in carrying that purpose and plan into effect.”
The important thing to get out of this study is that Jesus is much, much more than just a man, a religious teacher, or a martyr. He is what he claimed to be: the I AM of the Old Testament. He is able to make a Way of salvation. He speaks the Truth. He is able to give Eternal Life to those who place their faith in him as their Lord and Savior.
I and the Father are one.
(John 10:30 ASV)
Jesus saith unto him, I am the way, and the truth, and the life: no one cometh unto the Father, but by me.
(John 14:6 ASV)
Scripture used in this study is from The American Standard Version, Copyright, 1901 by Thomas Nelson & Sons