Inclusivism is the doctrine that while no one can be saved apart from Christ, one need not have conscious faith in Christ to be saved. So, for example, while a good Buddhist may not trust in Christ for his salvation, since he is a good Buddhist Christ applies the merits of His substitutionary atonement to him.
The NT is opposed to inclusivism. It is quite clear that one must exercise conscious faith in Christ to experience salvation:
John 3:14-18 And as Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up,  that whoever believes in him may have eternal life.  “For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life.  For God did not send his Son into the world to condemn the world, but in order that the world might be saved through him.  Whoever believes in him is not condemned, but whoever does not believe is condemned already, because he has not believed in the name of the only Son of God.
John 5:22-24 The Father judges no one, but has given all judgment to the Son,  that all may honor the Son, just as they honor the Father. Whoever does not honor the Son does not honor the Father who sent him.  Truly, truly, I say to you, whoever hears my word and believes him who sent me has eternal life. He does not come into judgment, but has passed from death to life.
John 5:37-40 And the Father who sent me has himself borne witness about me. His voice you have never heard, his form you have never seen,  and you do not have his word abiding in you, for you do not believe the one whom he has sent.  You search the Scriptures because you think that in them you have eternal life; and it is they that bear witness about me,  yet you refuse to come to me that you may have life.
John 6:40 For this is the will of my Father, that everyone who looks on the Son and believes in him should have eternal life, and I will raise him up on the last day.”
John 10:27-30 My sheep hear my voice, and I know them, and they follow me.  I give them eternal life, and they will never perish, and no one will snatch them out of my hand.  My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand.  I and the Father are one.”
John 14:6 Jesus said to him, “I am the way, and the truth, and the life. No one comes to the Father except through me.
John 20:30-31 Now Jesus did many other signs in the presence of the disciples, which are not written in this book;  but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.
Acts 4:11-12 This Jesus is the stone that was rejected by you, the builders, which has become the cornerstone.  And there is salvation in no one else, for there is no other name under heaven given among men by which we must be saved.”
Acts 10:43 To him all the prophets bear witness that everyone who believes in him receives forgiveness of sins through his name.”
Acts 11:11-14 And behold, at that very moment three men arrived at the house in which we were, sent to me fromCaesarea.  And the Spirit told me to go with them, making no distinction. These six brothers also accompanied me, and we entered the man’s house.  And he told us how he had seen the angel stand in his house and say, ‘Send to Joppa and bring Simon who is called Peter;  he will declare to you a message by which you will be saved, you and all your household.’
Romans 10:9-17 Because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved.  For with the heart one believes and is justified, and with the mouth one confesses and is saved.  For the Scripture says, “Everyone who believes in him will not be put to shame.”  For there is no distinction between Jew and Greek; for the same Lord is Lord of all, bestowing his riches on all who call on him.  For “everyone who calls on the name of the Lord will be saved.”  How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard? And how are they to hear without someone preaching?  And how are they to preach unless they are sent? As it is written, “How beautiful are the feet of those who preach the good news!”  But they have not all obeyed the gospel. For Isaiah says, “Lord, who has believed what he has heard from us?”  So faith comes from hearing, and hearing through the word of Christ.
1 Thessalonians 2:14-16 For you, brothers, became imitators of the churches of God in Christ Jesus that are inJudea. For you suffered the same things from your own countrymen as they did from the Jews,  who killed both the Lord Jesus and the prophets, and drove us out, and displease God and oppose all mankind  by hindering us from speaking to the Gentiles that they might be saved—so as always to fill up the measure of their sins. But wrath has come upon them at last!
1 John 5:11-12 And this is the testimony, that God gave us eternal life, and this life is in his Son.  Whoever has the Son has life; whoever does not have the Son of God does not have life.