1 Corinthians 1:18

For the message of the cross is foolishness (absurd and illogical) to those who are perishing and spiritually dead (because they reject it), but to us who are being saved (by God’s grace) it is (the manifestation of) the power of God.  

Have you ever tried to witness to someone and could tell that what you were saying about being saved was being rejected?  Plant the seed anyway.  Just as Jesus was rejected by the world, so shall we be as Christians.  We know the power of God and His word because it was what led us to salvation.  Pray for the door to be open.