In fact, salvation cannot happen apart from repentance!

Question: “What is repentance and is it necessary for salvation?”

Answer: Many understand the term repentance (from the Greek word metanoia) to mean “turning from sin.” This is not the biblical definition of repentance. In the Bible, the word repent means “to change one’s mind.” The Bible also tells us that true repentance will result in a change of actions (Luke 3:8-14; Acts 3:19). Acts 26:20 declares, “I preached that they should repent and turn to God and prove their repentance by their deeds.” The full biblical definition of repentance is a change of mind that results in a change of action.

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To repent, in relation to salvation, is to change your mind in regard to Jesus Christ.

If repentance wasn’t necessary for salvation, why then did Jesus command that repentance be preached to all nations? (Luke 24:47)?

Scripture verses on repentance

Roy B. Zuck writes:

Repentance is included in believing. Faith and repentance are like two sides of a coin. Genuine faith includes repentance, and genuine repentance includes faith. The Greek word for repentance (metanoia) means to change one’s mind. But to change one’s mind about what? About sin, about one’s adequacy to save himself, about Christ as the only way of salvation, the only One who can make a person righteous (“Kindred Spirit,” a quarterly publication of Dallas Seminary, Summer 1989, p. 5).

Is repentance necessary for salvation? – Bible.org

Another good article, The Gift of Repentance says:

Nevertheless, many people have succumbed to the notion that God does not require repentance in order to become a Christian. With the desire to make conversion to Christ as easy as possible, many pastors have decided not even to mention sin or repentance in their sermons. I recently heard about a pastor of a “seeker-friendly” mega-church in Houston, Texas, who doesn’t preach about sin in his sermons but instead just wants to “give people a boost for the week.” Perhaps someone should remind him that the first word recorded from the lips of our Lord Jesus was “repent” (Matt. 4:17). It is not as if repentance is secondary to the Gospel message, it is at the very heart of understanding the Gospel message. We can’t possibly understand our need for God’s grace unless we understand our need to repent of our sins. In Mark 1:14–15 we read: “Now after John was arrested, Jesus came into Galilee, proclaiming the gospel of God, and saying, ‘The time is fulfilled, and the kingdom of God is at hand; repent and believe in the gospel.’” Simply put, pastors and teachers are held to a more strict judgment (James 3:1), and if pastors do not preach repentance, then they themselves should repent.