Time will not currently permit me to share all of the reasons I say this, so I will bold the parts that are currently echoing in my mind.
Although Christ's summons to service is the most spiritually grand and noble way to live a life, it is typically as pedestrian as washing someone's feet. Richard Foster puts it starkly: 'In some ways we would prefer to hear Jesus' call to deny father and mother, houses and land for the sake fo the gospel, than His word to wash feet. Radical self-denial gives the feel of adventure. If we forsake all, we even have the chance of glorious martyrdom. But in service we are banished to the mundane, the ordinary, the trivial.'
The ministry of serving may be as public as preaching or teaching, but more often it will be as sequestered as nursery duty. It may be as visible as singing a solo, but usually it will be as unnoticed as operating the sound equipment to amplify the solo. Serving may be appreciated as a good testimony in a worship service, but typically it's as thankless as washing dishes after a church social. Most service, even that which seems the most glamorous, is like an iceberg. Only the eye of God ever sees the larger, hidden part of it.
Beyond the church walls, serving is baby-sitting for neighbors, taking meals to families in flux, running errands for the homebound, providing transportation for the one whose car breaks down, feeding pets and watering plants for vacationers, and - hardest of all - having a servant's heart in the home.
Serving is as commonplace as the practical needs it seeks to meet. That's why serving must become a Spiritual Discipline. The flesh connives against its hiddenness and sameness. Two of the deadliest of our sins-sloth and pride-loathe serving. They paint glazes on our eyes and put chains on our hands and feet so that we don't serve as we know we should or even as we want to. If we don't discipline ourselves to serve for the sake of Christ and His Kingdom (and for the purpose of Godliness), we'll 'serve' only occasionally or when it's convenient or self-serving. The result will be a quantity and quality of service we'll regret when the Day of Accountability for our service comes.