When Carlisle Floyd wrote "Susannah" just over 25 years ago, he created one of the classics in American opera. Portraying the tragic consequences cuased by the fanatical conduct of a moral majority, it presents an inside glimpse of the cruelties so often perpetrated in the name of religion.

The Baltimore Opera gave the second of three performances of "Susannah" Saturday night at the Lyric Theater, where the closing performance will be given tonight. It is well worth the trip. The production is a tribute to Jay Holbrook, the recently named general manager of the Baltimore Opera, for the way in which it upholds the best of the company's traditions.

Musically, dramatically and scenically, this "Susannah" would be a credit to any company. First praise must go to Karen Hunt, who stepped into the title role on one day's notice when the soprano engaged for the part ran into a flu bug. She triumphed at every point, and when she reached the opera's lyric high point in the aria, "Come back, summer," she sang with ravishing effect to create moments of unbearable loveliness.

Hunt was surrounded by a large cast of outstanding caliber. James Morris is ideal in appearance and voice for the Rev. Olin Blitch, one of those revival preachers who can't keep his hands off the pretty young girls in his congregation. The role of Little Bat demands a special kind of dramatic and vocal authority, depicting a rather slow-witted but randy kid. Anthony Laciura was completely believable in both action and singing.

Jacques Turssel sang Susannah's father with outstanding art. And the company found perfect quartets for those dirty old men out of the Bible, the ones who spied on Susannah and made all the trouble, and their wives. it is hard to think of a more vindictive-sounding Mrs. McLean, the most vicious woman of New Hope Valley, Tenn., then Charlotte Dixon, as she spat out her famous line, "I wouldn't tech those peas o'hern."

The staging by Bliss Hebert was convincing, the costumes of John Leymeyer ideal for the characters involved, and, as ususal, the wigs of Charles Elsen, notably those for Susannah and Little Bat, were perfect icing on the cake. Anton Coppola conducted strongly, if without quite the ultimate thrust in certain. passages. The chorus and members of the Baltimore Symphony Orchestra were highly satifying.