The first few that come to mind are:
St. John 1:1: “In the beginning was the Word, and the Word was with God, and the Word was God”
St. John 20:28: “Thomas answered and said to him: My Lord, and my God”
St. John 8:58: “Jesus said to them: Amen, amen I say to you, before Abraham was made, I am”
“I am” is the very name that God gave to Himself when He appeared to Moses in the burning bush to indicate that He is the eternal, uncreated supreme being. When Our Lord said this of Himself, He was clearly indicating that He is God. This is why the Jews “took up stones” to kill him (John 8:59). The prophecy of Isaias 9:6, which is clearly about Our Lord, also proves that He is God:
Isaias 9:6: “For a child is born to us, a son is given to us: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counsellor, God the Mighty, the Father of the world to come, the Prince of Peace."
Referring to how the Jews preferred the murderer Barabbas to Our Lord and had Him crucified, St. Peter says:
Acts of the Apostles 3:15: “But the author of life you killed…”
The author of life is God. Thus, Our Lord Jesus Christ is God. There are many other passages, such as the following:
Apocalypse 1:13, 17: “And in the midst of the seven golden candlesticks, one like to the Son of man… And when I had seen him, I fell at his feet as dead. And he laid his right hand upon me, saying: Fear not. I am the First and the Last, and behold I am living forever and ever…”
Colossians 2:6-10: "As therefore you have received Jesus Christ the Lord, walk ye in him; Rooted and built up in him, and confirmed in the faith, as also you have learned, abounding in him in thanksgiving. Beware lest any man cheat you by philosophy, and vain deceit; according to the tradition of men, according to the elements of the world, and not according to Christ: For in him dwelleth all the fullness of the Godhead corporeally; And you are filled in him, who is the head of all principality and power:"
Some people are unaware that God describes Himself as “the first and the last” in the Old Testament.
Isaias 41:4: “I the Lord, I am the first and the last”
There are many other passages we could bring up, but the fact that Our Lord is God is also proven by what is called “implicit Christology.” This means that the manner in which Our Lord spoke showed that He is God.
St. Matthew 5:28: “You have heard that it was said to them of old: Thou shalt not commit adultery. But I say to you, that whosoever shall look on a woman to lust after her, hath already committed adultery with her in his heart”
Notice that Our Lord, commenting on the words and commandment of God Himself in Exodus 20:14, clearly puts His own declaration on the same level: "You have heard that God has said," ... "BUT I SAY," says Our Lord. This way of speaking shows that He is God.
One of the most powerful proofs from Scripture of the divinity of Jesus Christ is the following:
St. John 16:15: "All things whatsoever the Father hath, are mine."
That is to say that EVERY SINGLE thing that is of the Father is of Jesus, the Son, also. What are some things that are the Father's? How about His words as spoken through the prophets. Here are some of the WORDS OF THE FATHER that ALSO BELONG TO JESUS:
Isaias 43:11: " I am, I am the Lord: and there is no saviour besides me."
How interesting. "But wait!" You might say: Those are words of the Holy Spirit, not of the Father!
Okay, granted they are words spoken by the Holy Spirit of God, through the prophets. Does that mean they are not the Father's words? Let's see:
St. John 16:13: "But when he, the Spirit of truth, is come, he will teach you all truth. For he shall not speak of himself; but what things soever he shall hear, he shall speak; and the things that are to come, he shall shew you."
The Holy Ghost does not speak "of himself" but only that which He hears. Who is He going to hear it from? The only possible choices are either God the Father or God the Son. But even God the Son, we know, did not come to speak of Himself.
St. John 14:10: "Do you not believe, that I am in the Father, and the Father in me? The words that I speak to you, I speak not of myself. But the Father who abideth in me, he doth the works."
So all the words spoken by either the Holy Ghost, or God the Son ARE THE WORDS OF GOD THE FATHER, who abides in Jesus Christ. Therefore, all the words of God the Father (as St. John 16:15 clearly states, "all things whatsoever") belong personally to Jesus Christ just as they belong to God the Father.
The fact that Our Lord is God and man (one Divine Person with two natures) was held by the earliest fathers of the Church and is a truth which must be held by all who want to be saved and possess the true Faith:
From AD 108, St. Ignatius to the church at Ephesus: "Ignatius, who is also called Theophorus, to her who has been blessed in greatness through the fullness of God the Father, ordained before time to be always resulting in permanent glory, unchangeably united and chosen in true passion, by the will of the Father and of Jesus Christ, our God, to the church which is in Ephesus of Asia, worthy of felicitation: abundant greetings in Jesus Christ and in blameless joy." (Ephesians 1)
Pope Eugene IV, Council of Florence, Session 8, Nov. 22, 1439, ex cathedra: “Whoever wishes to be saved, needs above all to hold the Catholic faith; unless each one preserves this whole and inviolate, he will without a doubt perish in eternity.– But the Catholic faith is this, that we worship one God in the Trinity, and the Trinity in unity; neither confounding the persons, nor dividing the substance; for there is one person of the Father, another of the Son, another of the Holy Spirit, their glory is equal, their majesty coeternal... and in this Trinity there is nothing first or later, nothing greater or less, but all three persons are coeternal and coequal with one another, so that in every respect, as has already been said above, both unity in Trinity, and Trinity in unity must be worshiped. Therefore let him who wishes to be saved, think thus concerning the Trinity."
Pope Eugene IV, Council of Florence, Session 8, Nov. 22, 1439, ex cathedra: "It is also necessary for salvation to believe faithfully the incarnation of our lord Jesus Christ. The right faith, therefore, is that we believe and confess that our lord Jesus Christ, Son of God, is God and man. God, of the substance of the Father, begotten before the ages; and man, of the substance of his mother, born in the world. Perfect God, perfect man, subsisting of a rational soul and human flesh. Equal to the Father according to his Godhead, less than the Father according to his humanity. Although he is God and man, he is not two, but one Christ. One, however, not by conversion of the Godhead into flesh, but by the taking of humanity into God. One altogether, not by confusion of substance, but by unity of person. For as a reasoning soul and flesh is one man, so God and man is one Christ. He suffered for our salvation and descended into hell. On the third day he rose from the dead. He ascended into heaven and sits at the right hand of God the Father almighty. Thence he shall come to judge the living and the dead. At his coming all shall rise again with their bodies, and shall give an account of their own deeds. Those who have done good shall go into eternal life, but those who have done evil shall go into eternal fire."
1 St. John 2:23: "Whosoever denieth the Son, the same hath not the Father: he that acknowledgeth the Son hath the Father also."
From the Athanasian Creed: "But it is necessary to eternal salvation that he also believe faithfully the Incarnation of our Lord Jesus Christ. The right faith therefore is that we believe and confess that our Lord Jesus Christ, the Son of God, is God and Man."
The Bible also teaches that the Catholic Faith is the true faith of Jesus Christ, as do the Early Church Fathers. You need to learn the true Catholic Faith, and convert to it, or you cannot attain salvation.