Pope Francis and pope emeritus Benedict XVI have co-authored a religious text stating their opposition to gay marriage.

In an 82-page document released Friday by the Vatican, the two popes restated the Roman Catholic Chruch's definition of marriage as a “stable union of man and woman,” the AFP reported.

“This union is born of their love, as a sign and presence of God's own love, and of acknowledgment and acceptance of the goodness of sexual differentiation,” the text reads.

The religious text, called an encyclical, is titled Light of Faith (Lumen Fidei). Its central tenet is that faith should be considered a “common good.”

“Its light does not simply brighten the interior of the Church, nor does it serve solely to build an eternal city in the hereafter, it helps us build our societies,” the encyclical says.

Francis said that Benedict had “almost completed” the text before stepping down earlier this year.

The two popes, who both live inside Vatican City, also appeared Friday at a Vatican ceremony for the unveiling of a new statue.