The candles on the altar are extinguished during the BenedictusResponses sung by the professed sistersAt the altar of repose, before Tenebrae of Good FridayAt the end of the Office the last candle, representing Our Lord Jesus Christ, is hidden behind the altar. This illustrates the disappearance of the "Light of the World" (Jn VIII, 12) at Our Lord’s death.The Lessons are sung by the clericsThe sisters sing the psalms from their stallsAt the end of each psalm a candle from the fifteen-branched candlestick is extinguishedOffice of Tenebrae of Holy Thursday