The 5th century Church Father Ammonius of Alexandria, preaching on this text noted:

“In order to draw away the disciples after them.” Heretics strive to make the people their own instead of the Lord’s, so that they might boast in themselves...Paul himself checked this beforehand when he silenced and censured those who were saying, “I’m Paul’s; I’m Apollos’s; I’m Cephas’s,” since he did not want their faith to be explained by the name of a person but by Christ’s name; he wanted them all to be called Christians, even though they had been taught by different teachers. Accordingly, whenever all the teachers strive for the same goal of proclaiming the true faith, of profiting the students while suppressing their own names, they are called, by the same name, Christians.1

The fruit of false teachers, prophets and ravenous wolves is easy to spot. If they preach themselves, not Christ, then they’re wolves.

Wolves preach about their lives, their victories, their dreams, their visions, their ideas, the tips and tricks they’ve discovered to achieve success. Jesus, if He’s mentioned at all by them, is merely held up as an example to be followed. The goal of their preaching is to convince you to apply the pastor’s insights and life tips so that you can be successful, just like the pastor is successful.

Faithful teachers of the one true faith, on the other hand, are not like wolves but are like the apostle Paul who said:

“But we have renounced disgraceful, underhanded ways. We refuse to practice cunning or to tamper with God’s word, but by the open statement of the truth we would commend ourselves to everyone’s conscience in the sight of God….For what we preach is not ourselves, but Jesus Christ as Lord, with ourselves as your servants for Jesus’ sake.” (2 Corinthians 4:2, 5)

If you ever find yourself in a church where the pastor is preaching himself, not Christ, run! As a baptized sheep in Christ’s flock you must always remember that wolves are not harmless, they eat sheep! The pastor who preaches himself rather than Christ is working for the devil and is preaching himself and his congregation into the fires of hell rather than into Christ’s eternal kingdom. And when you hear the faithful preaching of Christ crucified and raised for sinners, then rejoice and give thanks for that faithful pastor through whom Jesus delivers His forgiveness and life and makes you a member of His own flock of dearly bought sheep.

http://higherthings.org/myht/articles/catechesis/markofafalseteacher