All religions share a single message

"All religions share a single message" is a common "liberal" response to the problem of multiple conflicting religions. The people who push this line are generally trying to encourage religious tolerance by marginalizing differences between religions and at the same time trying to promote communal faith. It would be startling if every religion ever invented had come up with the same principles of faith, wouldn't it? It might even get a few atheists thinking differently about this "revelation" thing.

However, this statement is a flat-out lie. Religions have disagreed about:
 * Whether there are any gods
 * How many gods there are
 * Whether these gods are human-like (physically, mentally, emotionally)
 * What these gods desire from human beings (if anything)
 * Most other qualities of a god or gods
 * Whether there is an afterlife, and what it's like
 * Whether reincarnation happens, and how it works
 * The importance of sacrifices
 * The importance of sin
 * The importance of connecting or unifying oneself with a "higher power"
 * The existence of witches, magic, or miracles
 * When (if ever) murder is justified
 * When (if ever) other types of violence are justified
 * Whether or not slavery is morally acceptable
 * Whether or not other religions are morally acceptable
 * When (if ever) religious/cultural outsiders should be treated equally to believers
 * Whether or not polygamy is morally acceptable
 * Every facet of the treatment of women
 * The treatment of gay and lesbian people
 * The treatment of transsexual and intersex people (and whether or not they have magical powers)
 * Whether or not drug use is sinful
 * Whether or not drug use is an integral part of worship
 * Whether or not sex is inherently sinful
 * Whether or not sex is an integral part of worship (and when)
 * How trustworthy prophets are
 * The importance of faith
 * The value of meditation (and what kind)
 * The value of prayer (and what kind)
 * Whether thoughts alone can be sinful
 * Whether blasphemy is sinful
 * Whether or not disease is sinful (one form of ritual uncleanness)

Beside the many disagreements between religions, the apparent "agreement" between religions is often unconvincing. Some agreements are meaningless because they are vague, culturally universal, and have nothing to do with religion (like "be nice to other people"). Others are not really shared between all religions. For example, a spiritual connection to the universe/God, even though it is a very vague "quality" for a religion to have, is not even universal. Many variants of animism don't even have any particular overarching concept to connect to in the first place, but rather are more interested in limited, "everyday" sorts of gods.