Saint Francis of Assisi (1181/2-1226) is one of history’s most venerated religious figures. Rejecting worldly concerns, he preached on the streets and amassed a large following that was later established as the Franciscan Order. He also founded the Order of St Clare and the Third Order of Brothers and Sisters of Penance. On his deathbed, he sang The Canticle of the Sun, a religious song which he had composed himself. The reference to Sister Death comes in the final verse:
Be praised, my Lord, through our Sister Bodily Death, from whose embrace no living person can escape. Woe to those who die in mortal sin! Happy those she finds doing your most holy will. The second death can do no harm to them. Praise and bless my Lord, and give thanks, and serve him with great humility.