Today's first reading tells the story of the first Deacons. While we now think of it as the lowest level of clergy. They were,in a sense, the first of the modern orders. As acts recounts it, the apostles needed to remain dedicated to teaching and that the needy in the Greek speaking part of the community was not being ministered to sufficiently. The apostles laid hands on and prayed over this new group of ministers called deacons.
As the church grew the order of presbyters (priests) would come into being and the successors to the apostles whom the scriptures call bishops.
But it is worth remembering that in the 21st century, even the man who is now Pope was once ordained a deacon, and never leaves behind that ministry to serve the most needy.