Pope Emeritus Benedict XVI’s condition is serious but stable, the Vatican said on Thursday.

“The Pope Emeritus was able to rest well last night; he is absolutely lucid and alert, and today, although his condition remains serious, the situation at the moment is stable,” Vatican Press Office Director Matteo Bruni told journalists Dec. 29.

“Pope Francis renews his invitation to pray for him and accompany him in these difficult hours,” the spokesman added.

Pope Francis, at the end of his general audience on Dec. 28, asked for prayers for a “very ill” Benedict XVI, who, “in silence, is sustaining the Church.”

The Vatican confirmed later the same day that Benedict was under medical care following a decline in his health.

The Diocese of Rome announced it will offer a special Mass for Pope Emeritus Benedict XVI at the Basilica of St. John Lateran on Dec. 30.