"Known by Their Fruit" Test the fruit of a teacher's doctrine. If it agrees with God's word it is good fruit, if it doesn't agree with God's word it is rotten, poisonous fruit. Test the fruit your produce. If the fruit produced by the Holy Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Such fruit comes as we daily remember our baptism, crucifying our sinful nature by daily contrition and repentance, and rejoicing that, through baptism, God has united us with Jesus in his live and death.