Matt. 16:6,12Then Jesus said unto them, Take heed and beware of the leaven of the Pharisees and of the Sadducees.
12Then understood they how that he bade them not beware of the leaven of bread, but of the doctrine of the Pharisees and of the Sadducees.
Jesus condemned the Pharisees for what they taught. Not that they taught. He was concerned about the content of their teaching (as well as their personal sins) because they greatly harmed other people.
Jesus taught an awful of doctrine as well. “And he taught them many things by parables, and said unto them in his doctrine...” (Mark 4:2) “And they were astonished at his doctrine.” (Luke 4:2) “When Jesus had ended these sayings, the people were astonished at his doctrine.” (Matt. 7:28)
We teach these same doctrines because it is the word and will of God. “Jesus answered them, and said, My doctrine is not mine, but his that sent me. If any man will do his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself.” (Jn. 7:16,17) Today many are surprised to see such doctrinal teaching, but the true gospel has always been taught and advanced by teaching its precepts.
So Timothy was taught, “charge some that they teach no other doctrine.” (1 Tim. 1:3) Speak against all “that is contrary to sound doctrine.” (1 Tim. 1:10) “Take heed unto thyself, and unto the doctrine; continue in them: for in doing this thou shalt both save thyself, and them that hear thee.” (1 Tim. 4:16)