Religion has been a strong force in humanity since the first cavemen. Man has always and will always look at the world and ask why. Why does lightning happen, or crops fail Nobody knew and so religion was born. If humanity did not cause it then something did so we created the gods or the gods created us. IT all depends on your point of view. Religion has many benefits and many flaws.
One benefit of religion over atheism is it can act as a unifying force. Through out most of history when people have lost everything but their lives they have had fate in something. The early Jews where conquered and enslaved. Yet they had such faith in Yahweh they survived it as a culture and people. Later when the early Christians where hunted, persecuted, and fed to lions. Most did not give up their belief in Jesus.
Instead, they continued on believing in Christ. Knowing that if, they were caught what awaited them. Thousands died gory painful deaths that robbed many of their dignity but they stuck with it because they believed in goodness and compassion that the Old World lacked. A second benefit of religion is that it can be a moral guideline to raise the next generation. People hate to be told what they cannot do and need a reason. Religion, which has the ability to punish someone, even after death.
Religion acts like guideposts so we can judge how well we have lived our lives. The faith in an almighty being fills a void that all people have. The are many things that can fill that void such as friends, a hobby, alcohol, drugs, or other things to numerous to name. Unfortunately, like all things in life, religion has its other half. This half is dark and can potentially destroy a person or a whole group.
One example can be overly religious people or groups that have been taught to hate instead of love. Almost all-terrorist groups in the Middle East use the Allah as away to justify their gruel attack on others. They hate another group so completely for crimes long past or imagined. These people willingly commit foul acts of cruelty without a second taught. This leads me to the second downside of religion. Religion is a powerful tool that many people use.
Unforturntattely some use it so much they can no longer think for themselves. They become so dependent that they no longer are capable of judging actions for themselves. So if someone they recognize as religious leader tell them to blow up that building, they go home strap a bomb to there chest and BOOM! Without questioning why they deserved to die, they killed them. Maybe they did have a reason but they rationalized the final act that their god would take them to their heaven.
Is religion generally good or evil Personally, I think that like all things in life it depends on the individual person. Most religions are generally looking out for the welfare of their people and guide them to a better life. So I cannot fault that but since it is a man made, and administered institution it has its faults. Personally, I take religion with a grain of salt. I look at what I am told to do and compare it to what Jesus, Buddha, or Lao- said and then make my own decision.