K.H.
My children are much younger so I cannot say I've been through this with them but I went through similar situations as a high school student. I am strong in my Christian faith and did/do not like profanity either. I was very involved in my youth group and that alone gave me the strength and character to deal with "bullies." Since your son is going through a similar situation it might comfort him to know that it is normal to be persecuted. In Matthew 5:11-12 Jesus says "Blessed are you when people insult you, persecute you and falsely say all kinds of evil against you because of me. Rejoice and be glad, because great is your reward in heaven, for in the same way they persecuted the prophets who were before you." If your son can continue to be loving towards them when the bully him, they will notice a difference and gain respect for him (as long as the bullying is not physical, in which case the school obviously needs to get involved). I can say that not letting them know it affects you and continuing to show love is not always easy but it works. Your son may find comfort (as I did) in Scripture...1 Peter 4:8, James 1:2-18, Romans 8:28-39 (especially verse 31).