...
I resent it because religion has instituted itself as the interpreter of morality and ethics that come from God as it's source. As we all know, this is incredibly dangerous and provides an easy pathway to abuse. Most religions claim that their morality and ethics come from their god - an outside source that cannot be accessed to provide real world checks for veracity. God's will and God's plan are ambiguous, and the goal far too often is in conflict with real world problems, because the goals of changing the behaviors of their flock is to ensure their entrance into the afterlife, not necessarily to reduce suffering and encourage happiness in this life. Reaching heaven is paramount to most that truly believe in their religion. This provides a dangerously easy way to get to a state where "the ends justify the means".
Because the goals of a religions ethics and morality aren't necessarily bound to the real world and it's problems, it often comes into conflict with actions and behaviors that could provide a mechanism for change to lessen the world's suffering. It bypasses empathy, creates scapegoats and does not correctly assign responsibility where it belongs.
The ethics and morality espoused by religion is too slow to adapt to the changing circumstances in society. It slows down moral and technological progress, all the while claiming that it's system of morality is superior to all others. They claim their system will provide the greatest amount of happiness if their tenets are followed. Because of the deference our society gives to religion, this is all too often taken at face value, and never challenged. When it is finally challenged, which is taboo, the only rationalization needed by the religion for their position is that they do what they do because that is God's will and provides a path to heaven. It's an answer for every challenge, it's not falsifiable, and therefore useless. Yet society takes it as (if you'll excuse the pun) gospel.
So we have a system that is merely an echo chamber for every possible negative human flaw that has no real world checks and balances. Prejudice, fear, anger, suspicion, hate, ignorance, misogyny - all are justified because God of course always happens to agree with his followers. Look at what the Catholic church has become, look at Islam in the Middle East, look at the protestants here in the U.S. They are all bent on acquiring power, wealth, and dominating their fellow humans; the very humans that often actually have a superior morality to the unconscionable men they blindly follow, and follow them they do because they sincerely want to be good people, yet they empower some of the greatest barriers to actual moral progress ever known to exist on planet earth.
This link of religion to morality MUST be broken, or we shall surely have hell on earth while everyone is trying very hard to reach a fictional heaven. Since the reality is that this life is all we get, our only shot, this is especially tragic.