A disciple is a student – one who is a learner. This learner is a follower of a teacher. Inherent in the concept of a disciple is that the student is in a position of subjection to a higher authority, the teacher. The student is to learn from that teacher, and such learning involves listening and obedience. Failure to fulfill one's duties as a student rightly results in discipline. Jesus said, "If ye continue in my word, then are ye my disciples indeed" (John 8:31). There could hardly be any controversy that a true disciple is a follower of Jesus.
The controversy lies in the identity of a disciple. Are all believers disciples? Or is discipleship a second-stage, advanced level for those who want to go deeper in their relationship with Christ?
To be sure, being called a disciple does not ensure salvation. But, on the other hand, to be saved is to a disciple, contrary to assertions by teachers who deny the necessity of trusting Christ as Savior and Lord.
Jesus recognized the fact that some [so-called] disciples were not true believers. Notice his words in John 6:64-66 and how some of these disciples reacted:
But there are some of you that believe not. For Jesus knew from the beginning who they were that believed not, and who should betray him. And he said, Therefore said I unto you, that no man can come unto me, except it were given unto him of my Father. From that time many of his disciples went back, and walked no more with him.
Although Jesus recognized that some who were called disciples were not true believers, other statements of His indicate that true believers will truly be disciples. In commenting on John 10:27, "My sheep hear my voice, and I know them, and they follow
me," D. L. Moody observed:
Christ's sheep have two marks: –
(1.) In their ears, "They hear my voice;"
(2.) In their feet, "They follow me."
When Jesus invited people to come to Him, it was not first to believe and at some later time become disciples, but to believe and become disciples:
Come unto me, all ye that labour and are heavy laden, and I will give you rest. Take my yoke upon you, and learn of me; for I am meek and lowly in heart: and ye shall find rest unto your souls. For my yoke is easy, and my burden is light. (Matthew 11:28-30)
Notice also the Great Commission:
And Jesus came and spake unto them, saying, All power is given unto me in heaven and in earth. Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: Teaching them to observe all things whatsoever I have commanded you: and, lo, I am with you alway, even unto the end of the world. Amen. (Matthew 28:18-20)
Here Jesus says that discipleship is an integral part of evangelism. In the English Standard Version, the rendering of the KJV "teach all nations" in Matthew 28:10 is given this way: " make disciples of all nations." Christ could have said, "Make believers," but said, "make disciples." These disciples are to be taught by the followers of Him who has all power (authority) to keep all His commandments. Is discipleship an option for advanced Christians? Is it an extra credit track? No. Discipleship is part and parcel of what it means to be a true believer in Jesus Christ.
The issue of what role faith and works play in salvation is a matter of eternal consequence. It is not a game of words in Wonderland. What we mean by these important terms and how we interpret the Bible will inform our understanding of salvation, how we live our own lives, and how we communicate the Gospel to others. It is about the Gospel – the good news of Jesus Christ. We need to know its meaning. That meaning is not determined by teachers who act like theological Humpty Dumpties from the fantasy land of Alice. We gain understanding by a thorough reading of the Scriptures, whose source is the God of the Word. This God has the right to determine meaning, and has spoken clearly and revealed that meaning in regard to the role of faith and works in salvation. He is not playing word games with us.
 D. L. Moody, Moody's Notes From My Bible (Chicago: The Bible Institute Colportage Association, 1895), 139.