# lay on his couch

"sat eating his special meal." This probably refers to one of the couches on which people would lie around a table at a banquet. You could translate using the common word for what people do with their bodies when they eat special meals.

# nard

an oil that people got from the expensive nard or spikenard (valerian plant with small pink or white flowers) and used to make their skin soft and to have a pleasant odor.

# emitted its fragrance

"gave off its good smell"