Never let anyone tell you that the Trinity isn’t biblical. And never be unapologetic in your belief in the Trinity. Granted, the word “Trinity” isn’t used in the Bible, but the doctrine is clearly presented consistently throughout the Bible. In today’s Bible reading, John presents the Trinity in its beauty.
Believers believe in a triune God, that is, One God revealed simultaneously in three persons: God the Father, God the Son, and God the Holy Spirit. Don’t fall for the heresy that says the Father became the Son Who became the Holy Spirit. The Bible teaches that all three have co-existed simultaneously through eternity past and will continue to co-exist simutaneously through eternity future.
Look at John 16:5 and John 16:7. Look at Genesis 1:1-2 and John 1:1. Also, look at Jesus’ baptism in all of the Synoptic Gospels. (Matthew 3:16–17; Mark 1:10–11; Luke 3:21–22) All of these passages speak of the ever-present Trinity as separate persons. Neither is another, but all are fully God, as is illustrated in the diagram above. If you’d like to read more about the Trinity, check out this article from the Gospel Coalition.
One of the beauties of the Trinity is that it models perfect submission. And if there is submission in the perfect Godhead, submission is a good thing! John 16:13–15 and John 16:26-28 show that the Spirit submits to and glorifies the Son and the Son submits to and glorifies the Father.