"But after the meal, now and at the hour of our death, and at midday and at six in the evening, now and at the hour of our death."

The times of day would be prayer times in the convent.

The Hail Mary contains the line 'Holy Mary, Mother of God, pray for us sinners, now and at the hour of our death'.

The Catholic Encyclopaedia contains an article on the Hail Mary.

The Hail Mary is an integral part of the Rosary: