There are several literary devices employed in Yeats's poem, but one theme that he often employs is that of the journey of life. This journey is presented in spiral imagery that explores the human condition, focusing on time, change, love, age, and wisdom. "The Ballad of Father Gilligan" describes the journey of Father Gilligan's life which involves his visits to the dying from the point at which "the moth-hour went from the fields/And stars began to peep" to "...the time of sparrow chirp/When the moths come once more." In these lines the spiral imagery connotes time. The metaphor of the moths is a comparison between the Irish moths that appear at the beginning and the end of twenty-four hours. The poor would express time in some manner like this as no one would own a watch.
This poem is written as a traditional Irish ballad that employs the ballad quatrain form: eight syllables in the first and third lines which do not rhyme; then six syllables in the second and fourth lines which do rhyme. Like all ballads, this one tells a story. Father Gilligan is a priest who has been ministering to the dying Irish people during an epidemic; however, he is so overcome with fatigue that he falls asleep while kneeling and praying by his chair. When he awakens it is the next day, and he jumps up fearing that he has failed to bring the Last Rites to one of his parishioners. Hastily and with guilt, he jumps on his horse and races to the man's home, but the man has already died.
"Father! You come again."
The pries realizes that God has sent an angel to minister to the dying man in his place. In gratitude, he kneels and in an allusion, the priest acknowledges God's help:
He who hath made the night of stars
For souls who tire and bleed,
Sent on of His great angels down
To help me in my need.
Finally, the "night of stars" is a metaphor (an unstated comparison) for the peaceful death after one has received the last rites, or Extreme Unction, that cleanses a person's soul.