9, 10. (a) What can be learned from the example of a Christian couple who failed to hold a good conscience? (b) How can we prevent our conscience from becoming seared?

⁹ Today violence and sexual immorality pervade movie and TV presentations as well as the printed page. If we feed our mind on such, our conscience can gradually become seared. This happened to a young Christian couple who committed fornication shortly before their wedding day. “I think it had to do with what we had been watching on TV,” admitted the young woman. “You see persons all the time necking and petting, so it does not seem to be serious. You get used to it. So we started doing it. If I had only thought more about how serious it was!” Before she realized it, she lost her good conscience. The young man added: “I also had a problem with masturbation, and this sears your conscience so it is not so hard to engage in necking and petting and then finally in fornication.” Though they seemed to be setting a good example before others, what they watched for entertainment, together with a secret unclean practice, had worked toward deadening the conscience just as flesh is cauterized by repeated touches from a red-hot branding iron.​—1 Timothy 4:2.

11, 12. (a) What warning is given at 2 Timothy 2:20, 21? (b) How can you heed that warning?

¹¹ The apostle Paul writes: “In a large house [the congregation] there are vessels not only of gold and silver but also of wood and earthenware, and some for an honorable purpose but others for a purpose lacking honor. If, therefore, anyone keeps clear of the latter ones, he will be a vessel for an honorable purpose, sanctified, useful to his owner, prepared for every good work.” (2 Timothy 2:20, 21) Our emotions and conduct are greatly affected by those whom we choose as friends. Obviously, unbelievers are not the best associates. But Paul here shows frankly that even within the congregation there could be persons who are undesirable associates. True, you may find such ones fun to be around, but their influence will never help you to “flee from the desires incidental to youth” or to develop godly devotion. Reach out for upbuilding associates within the congregation. Paul continues in 2Ti 2 verse 22: “Pursue righteousness, faith, love, peace, along with those who call upon the Lord out of a clean heart.”​—Compare Philippians 4:8, 9.

¹² Take the case of one Christian youth who, despite godly training, was always getting into trouble. “It was largely because of the people I was associating with,” she said. When she saw her life becoming a failure, she changed her friends.