Jesus was the master teacher He taught His disciples the facts they needed to know and made applications which they could not miss. He answered their questions and explained what they did not understand. Yet wisely, He did not go deeper than they were able to comprehend (John 16:12). Having taught them, He sent them out for practice teaching (Matthew 10). He encouraged them by telling them they would do greater works than He (John 14:12) referring likely to their wider sphere of teaching.
The skill of Jesus is demonstrated in the actions of the apostles after He left them. They traveled to the uttermost parts of the earth, they did write books and their lives were so reflective of His nature that people everywhere "realized that they had been with Jesus" (Acts 4:13).
Even this, however, does not fully explain His influence in our world today.