Before going anywhere with this topic, we are forced to reconcile one key point. None of us are experts on all religions. Many of us have experiences with other religions, but we can not assume to be experts on all forms of religion and theology. But what we can do is look at what we believe and consider why we have that belief today.
Many people believe the way they do because they were brought up in an environment that practiced the religion that they have today. Many believe what they do because they have had some sort of experience that ‘awakened’ them to the concept of a God or spirituality as something real. Others have put into practice the teachings of a specific religion and have found what they see as truth and validation for those beliefs. But, for others, they simply haven’t had that experience that told them that God (or a particular religion) is real. So without nitpicking a specific religion, we can already draw some lines in the sand about what is right.
We know that many religions share a common concept of good and evil. Many of the practices and values could be considered good across these religions. We should love one another, don’t steal, don’t murder, care for the poor, meditation, etc. We could probably make a very large list of valuable ideas and practices that could be shared across these religions.
Enter Jesus. Many believe that Jesus was real. Many also believe in his teachings. If you, however, believe in his teachings, must wrestle with his claims of deity. He also claimed to be the only way to God (John 14:6). This sets Christianity apart from many other religions. It isn’t about earning your way to God through good deeds or daily practices. It is about accepting that you (or anyone) can not do it on your own. If you believe that you can earn your way to God or heaven, or whatever the good side of the afterlife is, then you are not really accepting the teachings of Jesus. It is because Jesus is at the focal point of Christianity that Christians ultimately think that they are uniquely right. Taking Jesus seriously logically leads to the conclusion that he is the only way to be restored to God and makes Christianity uniquely true. To argue for any sort of shared truth among religions rejects Jesus’ claims to be the only means of restoration to God.