Can you identify the region in which a type of fruit was grown, or whether it is ripe or not, sour or sweet just by looking at it? I can for some fruit, but definitely not all fruit. Jesus preached in this continuation of the Sermon on the Mount, that His disciples would know false prophets by their evil fruit. What is evil fruit? It manifests as ungodly lifestyle choices and conversations, heretical preaching and teaching, and the lack of Christ-like disciples produced from their ministry. Jesus cannot lie. If you are His disciple, you will know who is producing good fruit and who is producing evil fruit.