Henri J.M. NouwenThe question is not to prepare [for ministry] but to live in a state of ongoing preparedness so that, when someone who is drowning in the world comes into your world, you are ready to reach out and help. It may be at four o'clock, six o'clock, or nine o'clock. One time you call it preaching, the next time teaching, then counseling, or later administration. But let them be part of your life in God--that's ministering.
Source: Time Enough to Minister in the journal Leadership (Spring 1982)