So, they found out you had a couple of years of piano lessons when you were a kid, and now you’ve been recruited to fill in at the piano or keyboard in an emergency. If you don’t, they say, the hymns will just have to be sung—gasp—a cappella. Well anyway, that’s what happened to me. Now, a few decades later, I’ve jotted down some helpful hints that I’ve learned the hard way.

Remember that you are playing because there is no one out there who can do it as well as you can.

Moderate nervousness is good; it makes you more alert. Extreme nervousness only saps your energy and concentration. Don’t allow yourself to indulge in it. Focus on the job at hand.

In music, mistakes happen all the time. Get over it and get on with it. Most people don’t even notice. The few that do will admire your ability to keep going, seemingly unperturbed.

When choosing additional music for the offering, etc., pick something you are comfortable with. Having played a piece well once or twice at home doesn’t mean you’re ready to do it with the stress of playing it publicly.

If you can’t see the music well, you don’t have much chance of playing it well. Invest in appropriate lenses (measure from eyeball to music on the rack). Bifocals are too awkward and generally inadequate. Simply photocopying the music a little larger may suffice. Yes, it’s legal to do that in order to make the music more convenient to play.

Organize all the music you will be playing for a service in a binder. Use page covers and place tabs on the edges. Not only will page turning be easier, but notations on the tabs such as Prelude, Hymn 1, and Offering will keep you on course.

Write notes (musical and otherwise) right on your music—but only so many as can be taken in at a glance. On difficult passages, work out the best fingering and stick with it.

Tempo and melody should predominate. Try using a strong, rhythmic bass. Determine the best tempo for each hymn ahead of time, and don’t let a sluggish congregation drag you down. If there is no song leader, you’re it by default. You’re not accompanying at this point; you are the leader—so act like it. Of course, you will want to make adjustments if you notice everyone struggling to keep up. Don’t worry, though, if the congregation lags a split second behind you. That’s very common. (Many people, it seems, just like to hear the next note before they sing it.)

Unless otherwise noted or popularly understood, keep a strict tempo, but gradually slow slightly toward the end.

Play eighth notes distinctly. Don’t forget that, in addition to trying to sing those notes, the worshipers also have words to read and, hopefully, think about! You might even consider slowing ever so slightly when playing eighth notes, especially where each is assigned its own syllable, as in “Praise him! praise him! Jesus our blessed Redeemer!”

And please, count out the full measure at the end of each line. The singers are counting on that time to take a breath.

Generally, people are less inhibited in their singing when they don’t have the sense that they are singing a solo. Play loudly enough for everyone to able to hear you well. Trust me, if they can’t, they’ll just hold back until they can.

Using a hymn arrangement that is different from the one in the congregation’s hymnbook will likely confuse and irritate those who can read music and like to sing parts—and right now they’re your best friends.

Don’t fret about not being able to play fancy flourishes. You are there to serve, not dazzle. Your job is to be helpful, not impressive.

And finally, God gives gifts to his church, and one of yours is being able to accompany the congregation during worship services. Trust him also to give you the ability to use this gift, limited as it may seem to you, for his glory and the good of his church.

The author is the organist/pianist at Grace OPC in Fair Lawn, N.J. New Horizons, June 2012.