Salvation is found in no one else, for there is no other name under heaven given to men by which we must be saved. Acts 4:12
This is a bold and clear statement that must be responded to as either the truth to be accepted or a lie to be rejected. If salvation is found only in Christ, then it means that all other religions (attempt by man to connect with God) are false. Since the birth of the Church, Christians have been persecuted because of this claim that Jesus Christ is the only way to God. The Church, under the Roman empire paid direly for refusing to acknowledge Caesar as God.
Likewise, the Church today is persecuted and written off as arrogant and intolerant for not accepting other religions as valid ways to God. The world thinks we made up the claim about Jesus Christ being the only way. We can forgive their ignorance. But what do we say about church members who do not believe this claim from the Bible and think that all good people will go to heaven? Does our reluctance to go out and witness not show that we do not fully believe in the Bible? I believe the problem is not the unbelief of the unbelievers but rather the unbelief of believers who are not living as people who believe that Jesus Christ indeed is the only way, the truth and the life.
If we live out this truth at all cost, many people will believe also and be saved. When was the last time you told someone that Jesus Christ is your savior and Him alone is the savior?