First and foremost is a truly repentant heart, 2 Corin 7-10-11, a heart made pure through repentance and a working faith in love, purity, and sincerity, which is the purpose of the command.
A true denial of self, Luke 9-23, willing to count the cost, stand firm, forsake the world and its vain attractions, and follow in the footsteps of Jesus example.
A true disciple, will then stand against the onslaught of false teachers coming out of the churches today,
Jud 1:3 Beloved, although I was very eager to write to you about our common salvation, I found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints.
Most believe all you have to do to be a disciple is say a simple prayer, then you are instantly made a disciple of Christ, then alls you have to do is trust in the finished provision that Christ made on the cross for you.
This is far from the truth, Jesus came to set the captives free from the bondages of sin, John 8-32, and was our example to follow, we are commanded to be obedient, John 14-15, and avoid all appearances of evil.
There is a huge difference between those who just believe IN Jesus, and live a godless worldly life, and those who have repented, and living an obedient life on the narrow road.
Luke 13:24 "Strive to enter through the narrow door. For many, I tell you, will seek to enter and will not be able.
Remember many are called but few will choose to follow Christ on the narrow path, and count the cost!