The word disciple refers to a learner or follower. The word apostle means “one who is sent out.” While Jesus was on earth, His twelve followers were called disciples. The twelve disciples followed Jesus Christ, learned from Him, and were trained by Him. After His resurrection and ascension, Jesus sent the disciples out to be His witnesses (Matthew 28:18-20; Acts 1:8). They were then referred to as the twelve apostles. However, even when Jesus was still on earth, the terms disciples and apostles were used somewhat interchangeably.