Christians can be strong of character. But when it comes right down to it, Christians are only people. Yes, saved people with the power of the Holy Spirit working in our lives, but we are still susceptible to outside influences affecting us. Paul warns us in first Corinthians about how bad company can corrupt good character. It says in chapter 15, verses 33 and 34:
"Do not be misled: 'Bad company corrupts good character.' Come back to your senses as you ought, and stop sinning; for there are some who are ignorant of God - I say this to your shame."
Remember, we are to be in the world, but not of the world. It is true that Jesus spent time with unbelievers. He did this because those were the people who needed salvation. We are to do the same, but we should stay on guard against the influences that run contrary to what the bible teaches. We all have weaknesses, and you are probably aware of where you struggle most and what negative influences are most likely to lead you into sin. I encourage you not to willingly put yourself in situations where these negative influences can corrupt your Christian character. And if you are in a situation where your character is being corrupted, heed Paul's words - “come back to your senses as you ought and stop sinning”. Don’t be ignorant of God, but be vigilant for him.
“Bad company corrupts good character.” Some of us have an easier time standing in situations where others would easily fall. We all should know ourselves pretty well. We know where we are weak - where Satan can get a stronghold, and we know where we are strong - where the Holy Spirit can easily support us - even in the midst of worldly situations. Paul warns us about being ignorant. Yes, there is a mission field, but heed Paul’s warning. Don’t let yourself be corrupted by bad character. Know when to flee, know when to stand, and know when to fight - spiritually speaking of course.