Because these atheists can not accept that there is a higher power than them to answer too. In doing so, they feel that their beliefs and ways of life will be judged. They know they do wrong, but they need to convince their own mind that there is no GOD, so as to make an excuse to carry on with a clouded but content conscience throughout life. Mankind has many ways to reason his way out of bad and evil ways.
Remember it is simple to be bad, but it takes character and strength to be GOOD. The path to evil is wide and crooked, and the path of righteousness is straight and narrow...
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