Fact check: What year did the Catholic Church officially establish celibacy for priests?

1. Summary of the results

Based on the analyses provided, the Catholic Church officially established celibacy for priests in 1139 at the Second Lateran Council ^{[1] [2] [3]}. However, the historical development was more gradual than a single decisive moment.

The process began earlier with the First Lateran Council in 1123, which decreed that clerical marriages were invalid ^[4]. The universal requirement of celibacy was imposed upon the clergy with force in 1123 and again in 1139 ^[5], indicating that the 1139 council confirmed and strengthened the earlier decree from 1123 ^[4].

Multiple sources consistently identify 1139 as the definitive year when the Church took its stand in favor of celibacy, with the Second Lateran Council approving a rule forbidding priests to marry ^[3]. This practice has continued for almost a thousand years since its establishment ^[5].

2. Missing context/alternative viewpoints

The original question lacks important historical context about the gradual development of celibacy requirements. Before 1123-1139, celibacy was not a required or enforced rule for everyone ^[2], meaning married priests existed in the early centuries of Christianity.

The sources reveal that the Church was a thousand years old before it definitively established celibacy ^[3], indicating this was not an original apostolic practice but a later institutional development. This timeline suggests that for the first millennium of Christianity, priestly celibacy was not universally mandated.

The analyses also show there are contemporary discussions about potentially changing this rule, with some sources advocating for married priests ^{[6] [7]}. This indicates ongoing debate within Catholic circles about whether this thousand-year-old requirement should continue.

3. Potential misinformation/bias in the original statement

The original question itself does not contain misinformation, as it simply asks for factual information about when celibacy was established. However, the question's framing might imply that celibacy was always a requirement from the Church's founding, when in fact it was implemented over a thousand years after Christianity began.

The question also doesn't acknowledge the two-stage process (1123 and 1139) that some sources describe, potentially oversimplifying what was actually a gradual institutional change rather than a single moment of establishment.