What are you thinking about right this minute? Before you sat down to read this devotion what was on your mind? Were they good thoughts or impure thoughts? Our mind has to be trained to be Christlike. It has to be disciplined to "feed" it with good input and not garbage. Whatever we put in our minds is often the kind of person we are.
For instance, a constant "diet" of R rated movies full of cursing and crude humor may produce a mind and conscience seared like a hard heart. The more you take in the less it bothers you. Perhaps you get to a point where you feel it is normal.
A person who feeds their mind on pornography is also going to send their mind into a pit of destruction. When you know certain things are wrong you need to be disciplined to run the other way. Flee evil.
Many forces in the world today make sin and crude language seem common place. You watch television to a constant stream of "bleeps". What happened to pure speech and a clean heart?
Philippians 4:8(NIV) is a good verse to memorize. It says 'Finally brothers, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable-if anything is excellent or praiseworthy-think about such things.' Meditate on that scripture then ask God to help you discipline your mind for the kingdom of God.