People involved in ministry

An average church is filled with people doing jobs.
A great church is filled with people involved in ministry.
—Frederick Buechner
Pick the person who sees his work as ministry in the following story:

A long time ago, a traveler came upon a site in England where swarms of workers were building a grand church. The traveler saw several men digging a ditch. He stopped to ask three of them what exactly they were doing. The first replied, "Hey! I'm just doing what they tell me to do. All I care about it making a living to support my family." The second replied, "Me? I'm digging a ditch from here to that stake over there." But the third worker stopped, leaned against his shovel, and with a gleam in his eye, said, "I'm helping Christopher Wren build a great cathedral."

Thanks to Lindy Black for the quote and story.