Christ is our "master" (or "teacher"); we are His disciples (or students). Also, He is our "lord" ("ruler"); we are His servants (actually slaves). The disciple must believe what his master teaches, and the servant must do what his Lord commands. It is interesting to note that Christians are called disciples only in the four gospels and the book of Acts, never in the epistles. They are called His servants, however, throughout eternity (Revelation 22:3).

Source:

KJV Defenders Study Bible, by Dr. Henry Morris, Ph.D.
Publisher: Thomas Nelson
Language: English
DEF 10 ISBN 0-529-10444-x
DEF 10-1 ISBN 0-529-10445-8