Good humor is so important in running a rehearsal. When the stress of trying to make everything perfect gets so intense, it can actually detract from getting the hoped-for results. For a singer, the harder you try for perfection, the more stress you can feel. And the more intense the stress, the tighter and tighter your muscles can get. And when the muscles tighten, the tone quality gets pinched. And when the tone quality gets pinched, the conductor expresses in highly pointed language that you seriously need to fix it. And when the conductor is stressed, no one is happy. That is where a dose of good humor can come in handy.
A little laughter can relax tension in the muscles of the neck and jaw instantly. After the laughter come the deeper cleansing breaths so important to efficient, beautiful singing. It doesn't take much good humor to do the trick, and it is a marvelous tool to get the most out of your rehearsals. Don't let the seriousness become so intense that tension mounts out of control. Don't allow your rehearsals become agony. Try a little good humor to cut the tension.
Make the agony feel good!
The reason the word agony was so problematic is that it starts on a troublesome vowel for English speakers with no beginning consonant. The "a" as in "cat" is difficult because we American-speakers do not agree on the formation of that sound. Some sing the short "a" sound with a very flat, spread placement with a nearly closed jaw. Some try to imitate the British high placement but it comes across as a very swallowed, hooty sound in a deep throated "ah" with the jaw locked in an unnaturally dropped jaw placement. In fact, the proper placement for that sound will be "high" (tongue and soft palette) with the resonance focused towards the "mask" of the face with the jaw dropped to the "2-finger" measurement. Singers learn this placement as the Italian "a." (The "2 finger measurement" simply means that the singer should be able to fit 2 finger widths between his teeth when his jaw is dropped.)
Not many songs contain the word agony, but one notable song for Easter does, "Christ the Lord Is Risen Today" with text by Charles Wesley. I have included it in my arrangement of "An Easter Anthem Medley." This piece weaves together thematic material from "All Creatures of Our God and King" with pertinent verses of "He Is Risen" and "Christ the Lord Is Risen Today." It should be a nice addition to your Easter repertoire.