True disciples of Jesus Christ are those who follow Him in His Word. These are those who know His word. These are those who study His words day and night so that they could be well acquainted with the knowledge of His words. Such people cease every opportunity to learn the will of God. They are those who delight in the word of God. They are those who put all their energy to obey the doctrines of Jesus Christ.
To be a true disciple, one must obey His master in all things. He must cherish His master's words and do them. He must keep the instructions from His master. To be a disciple of Jesus Christ, we must live according to the doctrines of Jesus Christ. We must accept the ways of God. To become true disciples, we love what God loves and hate what He hates.
Everyone who obeys the doctrines of Jesus Christ is His disciple. It is not only the 12 apostles who are the disciples. All those who have come to accept and follow the doctrines of Jesus Christ are also his disciples.