ON THURSDAY and Friday nights this week, in the Library of Congress, baritone William Parker will join the Juilliard Quartet and pianist William Huckaby in a performance of Gabriel Faures song cycle, "La Bonne Chanson." Friday's 8 p.m. concert will be broadcast over WETA-FM.

In June 1870, Paul Verlaine's cycle of 21 poems called "La Bonne Chanson" was published in Paris. It was a wedding present for Mathilde Maute', whom the poet married on Aug. 11 that year. She was 17. He was 26, a heavy drinker on the way to an alcoholic's death, and a man sexually attracted to other men. He was also one of France's greatest lyric poets.

Throughout the cycle, Verlaine poured out his genuine love for the charming, innocent Mathilde. The eighth poem, which is the first of the nine that Faure' used in his cycle, begins, "A saint with her halo, a chatelaine in her tower, all that human words contain of grace and of love . . ." It is Verlaine's tribute to the beauty and domestic serenity he saw in the fiance' with whom he hoped to find a tranquillity he longed for -- some of the time.

Mathilde would later say that Verlaine was both Prince Charming and the Beast. In her memoirs, toward the end of a long life, much of which was spent in unhappy fear of and for Verlaine, she wrote, "For more than two years Verlaine did not once get drunk. I think he must have made a very commendable effort for love of me."

The effort collapsed soon after their marriage. Within a year, Verlaine was drinking heavily and becoming deeply involved with the gifted young poet, Arthur Rimbaud. In October of 1871, when Mathilde spoke disapprovingly of Rimbaud's stealing books from a store, Verlaine threw her out of bed onto the floor. One week later, their son, Georges, was born. When the baby was three months old, his drunken father threw him against a wall. The boy was not seriously injured, but Mathilde, correctly reading the future, realized she should leave her husband. By April 1874 they were legally separated.

None of this domestic tragedy is heard in Faure's exquisite settings of Verlaine's poems, for none of it appeared in the poet's words. Yet knowing what transpired so soon after the writing, it is possible to hear Verlaine asking Mathilde, in the fourth and fifth songs, for a kind of reassurance: "I walked the treacherous ways, miserably uncertain. Your dear hands were my guide . . . No sound save that of his own steps encouraged the traveler. Your voice said: 'Go on!' I can say again and always, in spite of dismal vicissitudes, that I love you! I love you!"

Faure' mirrors Verlaine's momentary certainty that all will be well. But with the rising octave in which he sets the final "N'est-ce pas?" -- "Is it not so?" of the last poem of Verlaine's cycle, the composer seems to emphasize the poet's desperate plea that the future be calm. The simple question is the poem's opening and closing.

Faure' left two versions of his song cycle, one for voice and piano alone, and the one Parker will sing this week, with string quartet joining the piano and voice. Both are filled with radiant instrumental textures and harmonic originality characteristic of the great composer.