The Lord inspired Moses to warn against adding or subracting from the Law given. Likewise the Lord Himself warned against imposters and deceivers who would enter the sheepfold by climbing up some other way instead of entering through the Door. Moreover the Lord also inspired Apostle Paul to warn against accepting any other gospel than that which was preached. Whether a man or an angel from heaven preach any other gospel, we were warned not to accept it. In addition, the Lord also warned against accepting any other revelation than that which was given through Apostle John. 600 years later an angel from heaven appeared to a man, revealing another gospel(Islam).
2 Corinthians 11:14 And no wonder! For even Satan himself transforms himself as an angel of light.
Deuteronomy 4:2 You shall not add to the word which I command you, nor subtract from it, that you may keep the commandments of the Lord your God which I command you.
John 14:6 Jesus said to him, "I am the way, the truth, and the life. No one comes to the Father except through Me.
John 3:18 "He who believes in Him is not condemned; but he who does not believe is condemned already, because he has not believed in the name of the only begotten Son of God.
John 10:1-2 Most assuredly, I say to you, he who does not enter the sheepfold by the door, but climbs up some other way, the same is a thief and a robber.
2 Timothy 3:13 But evil men and imposters will grow worse and worse, deceiving and being deceived.
John 10:7-10 The Jesus said to them again, "Most assuredly, I say to you, I am the door of the sheep. All who ever came before Me are thieves and robbers, but the sheep did not hear them. I am the door. If anyone enters by Me, he will be saved, and will go in and out and find pasture. The thief does not come except to steal, and to kill, and to destroy. I have come that they may have life, and that they may have it more abundantly.
Galatians 1:8 But even if we, or an angel from heaven, preach any other gospel to you than what we have preached to you, let him be accursed.
Revelation 22:18-19 For I testify to everyone who hears the word of the prophecy of this book: if anyone adds to these things, God will add to him the plagues that are written in this book; and if anyone takes away from the words of the book of this prophecy, God shall take away his part from the things which are written in this book.
1 Corinthians 1:18 For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God.
2 Timothy 2:25-26 In humility correcting those who are in opposition, if God perhaps will grant them repentance, so that they may know the truth, and that they may come to their senses and escape the snare of the devil, having been taken captive by him to do his will.
Deuteronomy 13:1-3 If there arises among you a prophet or dreamer of dreams, and he gives you a sign or a wonder, and the sign or the wonder comes to pass, of which he spoke to you, saying, 'Let us go after other god's' -which you have not known- 'and let us serve them,' you shall not listen to the words of that prophet or that dreamer of dreams, for the Lord your God is testing you to know whether you love the Lord your God with all your heart and with all your soul.
Psalms 16:4 Their sorrows shall be multiplied that hasten after another god: their drink offerings of blood will I not offer, nor take up their names into my lips.
Isaiah 44:6 Thus saith the Lord the King of Israel, and His redeemer the Lord of hosts; I am the first and I am the last; and beside Me there is no other God.
Isaiah 45:5 I am the Lord, and there is none else, there is no God beside Me:
Isaiah 42:8 I am the Lord: that is my name: and my glory will I not give to another, neither my praise to graven images.
1 John 5:7 For there are three that bear witness in heaven: the Father, the Word, and the Holy spirit: and these three are One.
John 1:14 And the Word became flesh and dwelt among us, and we beheld His glory, the glory as of the only begotten of the Father, full of Grace and Truth.
Zechariah 12:10 "And I will pour out on the house of David and the inhabitants of Jerusalem a spirit of grace and suplication. They will look on Me, the One they have pierced, and they will mourn for Him as one mourns for an only child, and grieve bitterly for Him as one grieves for a firstborn son.
Isaiah 9:6 For unto us a child is born, unto us a son is given; and the government will be upon His shoulder. And His name will be called Wonderful, Counselor, Mighty God, Everlasting Father, Prince of Peace.
Matthew 28:18-20 And Jesus came and spoke to them, saying, "All authority has been given to Me in heaven and on earth. Go therefore and make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all things that I have commanded you; and lo, I am with you always, even to the end of the age." Amen.
John 20:25-26 The other disciples therefore said to him, "We have seen the Lord." So he said to them, "Unless I see in His hands the print of the nails, and put my finger into the print of the nails, and put my hand into His side, I will not believe." And after eight days His disciples were again inside, and Thomas with them. Jesus came, the doors being shut, and stood in the midst, and said, "Peace to you!" Then He said to Thomas, "Reach your finger here, and look at My hands; and reach your hand here, and put it into My side. Do not be unbelieving, but believing."
Colossians 1:15-17 He is the image of the invisible God, the firstborn over all creation. For by Him all things were created that are in heaven and that are on earth, visible and invisible, whether thrones of dominions of principalities or powers. All things were created through Him and for Him. And He is before all things, and in Him all things consist.
Revelation 22:12-13 Jesus testifies to the Churches "And behold, I am coming quickly, and My reward is with Me, to give to every one according to his work. I am the Alpha and the Omega, the Beginning and the End, the First and the Last."
John 8:58 Jesus said to them, "Most assuredly, I say to you, before Abraham was, I AM."
John 5:46-47 For if you believed Moses, you would believe Me; for he wrote about Me. But if you do not believe his writtings, how will you believe My words?"
John 8:24 That is why I said you will die in your sins; for unless you believe that I am Who I claim to Be, you will die in your sins."