Friday of week 2 in Ordinary Time
There is a masterplan of salvation. The Church calls it "salvation history". As God is eternal, he also moves in time together with his children, the people of God till his plan is fulfilled.
In the time of Jesus, the Messiah starts working on the plan by calling his followers or "disciples". In due time, they would be regarded as "apostles" meaning, "sent forth".
Going back to the first reading, the author writes "The old covenant is not without fault." God chose to create a "new covenant" to be placed in the very hearts of men and women and in due time, reach its completion. By this time, people would not need to be instructed by others; God himself instructs them on what to do; they understand perfectly and follow willingly. Isn't this a definition of "disciple"?
The disciple is a disciple because:
1. he hears the one inviting to follow him and he responds;
2. he learns from the one he follows. He becomes one heart and one mind with him.
3. he is sent to do what his master tells him to do.
The old covenant is already gone. It's time for us of various generations after Christ to respond to fulfill his divine plan.