Popes, bishops, and priests married and sired children for over a thousand years after Christ Celibacy was first written into law for all priests in the 12th century at the First Lateran Council ( 1123 ).

The Concordat was confirmed by the First Council of the Lateran in 1123.

The Roman Catholic Church recognizes as ecumenical various councils held later than the First Council of Ephesus ( after which churches out of communion with the Holy See because of the Nestorian Schism did not participate ), later than the Council of Chalcedon ( after which there was no participation by churches that rejected Dyophysitism ), later than the Second Council of Nicaea ( after which there was no participation by the Eastern Orthodox Church ), and later than the Fifth Council of the Lateran ( after which groups that adhered to Protestantism did not participate ).

First Council of the Lateran ( 1123 ) addressed investment of bishops and the Holy Roman Emperor's role therein.

The First Lateran Council was convoked to confirm the Concordat of Worms.

The Concordat of Worms and the First Lateran Council changed forever the belief in the divine right of kings to name the pope and bishops, and reshaped the nature of church and state forever.

Texts of the First Lateran Council may vary in both wording and numbering of the canons depending on source.

* Medieval Sourcebook: First Lateran Council: Canons with annotations

* First Lateran Council

Four disputes set the stage for an independent Bishopric of Utrecht: the Concordat of Worms, the First Lateran Council and Fourth Lateran Council, and the concession of Pope Leo X.

The Concordat was confirmed by the First Council of the Lateran in 1123.

To secure the confirmation of this Concordat of Worms, Calixtus II convened the First Lateran Council on 18 March 1123.

* First Council of the Lateran

* In accordance with the decision of the First Council of the Lateran, the archbishop of Compostela, Diego Gelmirez, declares the Crusade in Iberia against the Andalusians.

* The First Council of the Lateran confirms the Concordat of Worms and demands that priests remain celibate.

* First Council of the Lateran

The Investiture controversy from previous centuries had been brought to a tendentious peace with the Concordat of Worms and affirmed in the First Council of the Lateran.

* First Council of the Lateran

* Canons 6, 7, 11: Repeated the First Lateran Council's condemnation of marriage and concubinage among priests, deacons, subdeacons, monks, and nuns.

John of Crema had been sent to England not only to seek a compromise in the Canterbury-York dispute, but to publicize the decrees of the First Council of the Lateran held in 1123, which neither William nor Thurstan had attended.

* First Council of the Lateran

* The Canons of the First Lateran Council, 1123

The First Lateran Council ( 1123 ), a General Council, adopted the following canons:

Deemed a heretic by the Ecumenical First Council of Nicaea of 325, Arius was later exonerated in 335 at the regional First Synod of Tyre, and then, after his death, pronounced a heretic again at the Ecumenical First Council of Constantinople of 381.

A 4th-century miniature of the First Council of Nicaea | Council of Nicaea, which condemned Arius's teaching

By 325, the controversy had become significant enough that the Emperor Constantine called an assembly of bishops, the First Council of Nicaea, which condemned Arius ' doctrine and formulated the original Nicene Creed of 325.

* First Council of Nicea

The help which he wanted from the West was simply mercenary forces and not the immense hosts which arrived, to his consternation and embarrassment, after the pope preached the First Crusade at the Council of Clermont later that same year.

Amongst the Buddha's many disciples, Ānanda had the most retentive memory and most of the suttas in the Sutta Pitaka are attributed to his recollection of the Buddha's teachings during the First Buddhist Council.

At the First Buddhist Council, convened shortly after the Buddha died, Ananda was called upon to recite many of the discourses that later became the Sutta Pitaka of the Pāli Canon.

Prior to the First Buddhist Council, it was proposed that Ananda not be permitted to attend on the grounds that he was not yet an arahant.

He continued to teach and to represent the University, and participated in the First Council of Lyon in the winter of 1245.

Adoptionism was declared heresy at the end of the 2nd century and was rejected by the First Council of Nicaea, which defined the orthodox doctrine of the Trinity and identified the man Jesus with the eternally begotten Son or Word of God.

It was declared to be a heresy in 381 by the First Council of Constantinople, since Christ was officially depicted as fully human and fully God.

In 325, at the age of 27, Athanasius had a leading role against the Arians in the First Council of Nicaea.

In 325, he served as Alexander's secretary at the First Council of Nicaea.

Athanasius ' first problem lay with the Meletians, who had failed to abide by the terms of the decision made at the First Council of Nicaea which had hoped to reunite them with the Church.

Athanasius may have accompanied Alexander to the First Council of Nicaea in 325, the council which produced the Nicene Creed and anathematized Arius and his followers.

As a result of rises and falls in Arianism's influence after the First Council of Nicaea, Emperor Constantine I banished him from Alexandria to Trier in the Rhineland, but he was restored after the death of Constantine I by the emperor's son Constantine II.

* First Council of Nicaea

After the First Ecumenical Council at Nicea, the church structure was patterned after the administrative divisions of the Roman Empire wherein a metropolitan or bishop of a metropolis came to be the ecclesiastical head of a civil capital of a province or a metropolis.

However, early church documents, such as those of the First Council of Nicaea ( 325 ) had always listed the Pope of Rome first among the Ancient Patriarchs ( first four, and later five: Rome, Constantinople, Alexandria, Antioch and Jerusalem — collectively referred to as the Pentarchy ).