2 Thessalonians 2:10

And by unlimited seduction to evil and with all the deception of wickedness for those who are perishing, because they did not welcome love of the truth (of the gospel) so as to be saved (they were spiritually blind, and rejected the truth that would have saved them).

To keep ourselves from being seduced by the deception of wickedness, we must welcome and love the truth of God. We cannot let any gray areas into our hearts or let our brains calculate how much sin is acceptable for a believer. (The answer is 0). The more we allow sin to seduce our thoughts, the more effortless the fall to sin and destruction will be.