There are numerous barriers to belief in God.  This portion of the webpage tries to address some of the more prominent reasons why people don't believe, or depart from the faith.  Clearly, when we allow ourselves to be enticed by sin because of our desires, and we become involved in sinful behavior, then we grow callous toward that behavior, and callous toward God.

13 Let no one say when he is tempted, "I am being tempted by God," for God cannot be tempted with evil, and he himself tempts no one. 14 But each person is tempted when he is lured and enticed by his own desire. 15 Then desire when it has conceived gives birth to sin, and sin when it is fully grown brings forth death. James 1:13-15 (ESV)

It is clearly possible for us to oppose some sinful behavior, but then, for numerous reasons, we stop opposing it, then we evolve to the point of quietly approving the sin, and then openly defending the sin.  This is where James says sin is fully grown, and brings forth (spiritual) death.  The beguiling element of sin is strong upon us, but we must oppose it.  Just as Jesus did not give into the temptations of Satan, so we too must stand firm.