Jesus took an opportunity that was before Him to teach a crowd that had gathered. This has become know as the "Sermon on the Mount". He used what was transpiring around Him as the fodder for the sermon. It says in the opening verses of Matthew 5 that when He was settled in a spot where everyone could hear Him, He opened His mouth to speak. What came out was not politically correct mush. The words of Jesus were direct and to the point. Like the business end of a sharp double-edged sword. That is actually what the phrase- "opened His mouth to speak" means. Jesus always wants to get to the heart and soul of a person and deal with matters of eternity. Today, allow His Word to pierce you soul.