Not everyone you encounter is your friend. Even if someone does something nice for you, that does not mean that they have your best interest at heart. You can't teach, reach, lead everyone. There will be a few that you will just have to keep in prayer and pray that they come to the truth. In saying that, please don't entertain foolishness. Just because it's not a sin doesn't mean it's good for you. There is a thing called a weight, weights bring you down. Remember that God can use you to bless anyone and He can also use them to bless you. Like I say in my email signature, "If you walk away feeling you've learned absolutely nothing, know that you've taught someone something!" That simply means not all lessons are for you. God can give you something that is sooo small to you but mean the world to someone else. He brings people in our path for us to teach and learn from, just as He does for others. So don't think that you are to reach everyone. He reaches them, you just do your duty and spread the good news and stay away from the weights and wrong doers. Two people on opposite sides of the fence can not share the same space for long and still have opposing views. At some point one will rub off on the other. If it is meant for you to entertain foolishness, GOD will call you to do so. He must call us to do certain things otherwise we will fall into the traps of satan. Only a few can go to the clubs to find and save souls, only a few can stand and preach the gospel on the corner, only a few can do missionary work in Iraq. We cannot choose ourselves. Let Him lead you. He will tell you if you should play with dirt, otherwise it will only get into your eyes.