Oddly enough, no prominent atheist is recorded as having said, "Faith in God is a crutch." Although the sentiment is related, it is religion that is compared to a crutch, not faith in God. Richard Dawkins believes that religion is a crutch for those who are afraid of blinking out of existence after death. The science fiction author Robert Heinlein wrote that "religion is a crutch for people not strong enough to stand up to the unknown without help." Former Minnesota governor Jesse Ventura says that religion is a crutch for "weak-minded people who need strength in numbers."
Is faith in God a crutch?
Christians are not weak-minded, but they readily admit their spiritual weakness without Christ. The fact is that we all have a spiritual impediment called sin (Romans 3:23), and we all need Christ's power to overcome it. Admitting the fact is nothing to be ashamed of. No one makes fun of a handicapped man who uses a crutch to compensate for his physical disability. Neither should anyone ridicule a Christian whose faith compensates for his spiritual disability. There's nothing wrong with a needy person seeking help.
To say that religion is a crutch is to say that we must stand on our own power, to see the world as a cold, empty place and deal with it accordingly. To the materialistic atheist, spurning religion includes the belief that death is merely ceasing to exist. Or, as Heinlein said, going into the unknown. A common view among atheistic sociologists is that fear of this "unknown" caused people to create myths of an overseeing, beneficent deity who carries out a beneficent plan for death. Atheists tend to think that, without this myth, most people would be so overwrought with the fear of death that they would be unable to function in life.
The idea of God as an imaginary coping mechanism began with Sigmund Freud. The famous neurologist and psychoanalyst was an atheist and could not accept the possibility that God might actually exist. He believed that the struggles of life and the lack of strong, loving father figures inspired the construction of an imaginary Father-God. This Father-God would provide for all the psychological needs of the deluded. The biggest struggle in human life is death, and later atheists latched onto the fear of death as the primary impetus for a make-believe story that made everything all right.
There are some problems with the theory. If the fear of death is truly universal and is the cause of all religion, then the selection of world religions isn't very satisfying. If humanity is so afraid of death that they have to come up with a fake belief system, why is religion so complex? A belief system destined to allay the fear of death should simply involve dying and arriving in paradise. Instead, nearly every belief system in the world somehow ties acts performed during life to rest in the afterlife. If death were the primary concern, getting to a favorable afterlife would probably be simpler.
This brings us to Ventura's quote and another common sociological theory about religion: religion was developed to control and unify people with a list of rules, a hierarchy of authority, and explanations for mystical occurrences. Many secular sociologists claim religion was developed as a necessary stabilizing force in society.
It's true that religion provides community, family, and friendship that are often lacking in the modern world. The need to belong is a powerful force, and religion fills that need nicely. It's conceivable that many people join religions not because they have objectively analyzed and agreed with all the tenets of the faith but because the traditions and rituals provide purpose and comfort. So, presuming God does not exist, the offer of community could reasonably explain the existence of religion.
But "presuming God does not exist" is a completely improvable assumption. There is substantial proof that God exists. If He didn't exist, religion would indeed be silly. But if God does exist, or if there is a reasonable chance that He exists, it is reasonable to desire to treat Him appropriately.
The "religion is a crutch" argument attempts to explain away religion by insisting on a hypothetical circumstance without touching the heart of the issue. It is true that many people come to religion because they want an answer for death or a feeling of belonging. But the argument does nothing to refute the existence of God or the actual legitimacy of any religion. The claim that "religion is a crutch" is a defensive judgment of motives that completely ignores the discussion of truth. It is also a proud, condescending point of view.
Jesus said, "Blessed are the poor in spirit" (Matthew 5:3); that is, those who humbly acknowledge their spiritual bankruptcy will receive God's compensation. Paul admitted his spiritual inadequacy but had the confidence that God's "power is made perfect in weakness" (2 Corinthians 12:9). For the Christian, faith is not a crutch; it's a necessary part of life (Romans 1:17).
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Can man live without God?
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Truth about Worldview and Apologetics