ROME — Striking the tone that once earned him the nickname “God’s Rottweiler,” Pope Benedict XVI in a stern Holy Thursday homily denounced “disobedience” in the Roman Catholic Church, chastising priests who sought the ordination of women and the abolition of priestly celibacy.

Referring to recent efforts by clerics in Austria and elsewhere, Benedict said that although such priests claim to act out of “concern for the church,” they are driven by their “own preferences and ideas,” and should instead turn toward a “radicalism of obedience” — a phrase that perfectly captures the essence of the theologian pope’s thought.

While there was nothing new in the contents of Benedict’s message, it was one of the strongest — and most direct — speeches of a seven-year-old reign that has more often been dominated by a sexual abuse scandal, repeated tangles with other faiths and a Vatican hierarchy in disarray. It also showed Benedict, who at almost 85 has been showing his age, in fighting form as a defender of orthodoxy, favoring a smaller church of more ardent believers over a larger community that relies on what he sees as diluted doctrine.

The pope, who once led the church’s doctrinal office, delivered his homily from a golden throne in St. Peter’s Basilica on the day priests recall the vows they made when ordained. He was clearly referring to an Austrian group called Preachers’ Initiative, which has issued a “Call to Disobedience,” asking the church to allow the ordination of women, to remove the obligation of priestly celibacy and to permit priests to give holy communion to divorced Catholics who have remarried without an annulment.