We tend to think about people searing their conscience when they go into sins: like lust, drunkenness and so on. However, in 1 Timothy 4 Paul’s concern is with them searing their conscience through legalism. People were forbidding marriage and eating of certain foods, and in doing so were searing their consciences. When you get a zeal for the Lord it is very easy for Satan to high jack that with a “do not taste, do not touch” mentality.
Mp3: http://illbehonest.com/weak-conscience-seared-by-legalism-ryan-fullerton