During his tenure as abbot he acquired additional land for the abbey, and may have helped to fabricate some charters—legal deeds attesting property ownership—to gain advantage in a dispute with the Archbishops of York.

For a short period following Becket's death the papacy kept Foliot excommunicate, but he was quickly absolved and allowed to resume his episcopal functions.

In addition to his role in the Becket controversy, Foliot often served as a royal judge, and was an active administrator and bishop in his different dioceses.

[5] William de Chesney, a partisan of Stephen's and a leading Oxfordshire layman,[6][a] was another of Foliot's uncles,[8] and Miles of Gloucester, Earl of Hereford, was a cousin.

The papacy continued to accept Stephen as king, and the pope ordered the English Church to make no changes to the status quo.

Matthew points out that Gloucester Abbey owed no military service in a feudal levy, which allowed Foliot to avoid choosing sides irrevocably.

Robert had argued that the Bible supported female succession, and quoted from Numbers, chapter 36, which allowed women to inherit, but prohibited them marrying outside their tribe.

[11] Another friend and ally from his abbacy was Theobald of Bec, the Archbishop of Canterbury, who during Stephen's reign was attempting to unite the English Church under his leadership.

[44] Theobald managed to secure peace between the parties,[45] saying that Foliot could not refuse to swear homage "to the prince approved by the papacy".

[51] During the later part of Stephen's reign Foliot was active in judicial affairs, including a case in 1150 involving sanctuary and his kinsman Roger, the Earl of Hereford, which ended up in the court of Archbishop Theobald.

[55] The art historian Hans J. Böker claims that Foliot began the construction of the Bishop's Chapel at Hereford Cathedral.

[39] His nomination had been put forward by the king, who wrote to the pope stating that Foliot would be more accessible as an adviser and confessor if he was in London, rather than in Hereford on the Welsh Marches.

[4] Foliot did though support Becket in the latter's attempt to prevent the Archbishop of York having his archiepiscopal cross borne in procession before him when visiting the province of Canterbury.

At the Council of Westminster called by Henry in October 1163 to deal with the issue, Foliot at first sided with the other bishops, who supported Becket's position and opposed the king.

[74] Foliot was sent, along with Roger, the Archbishop of York, Hilary of Chichester, Bartholomew Iscanus, the Bishop of Exeter, Roger of Worcester, the Bishop of Worcester, William d'Aubigny, the Earl of Arundel, and a group of royal clerks, to Thierry the Count of Flanders, Louis VII the King of France, and Pope Alexander III.

Foliot's delegation met with more success at the papal court; although they did not succeed in securing a decision in the king's favour, neither did the pope side with the archbishop.

[79] In early summer 1165, Pope Alexander III wrote twice to Foliot, ordering him to intercede with the king and protest the royal injunction against appeals to the papacy.

Foliot replied that the king respected the pope, heard his protests carefully, and that the archbishop had not been expelled, but had left of his own accord.

[83] Henry's response was to order the English bishops to appeal to the pope, which they did at a council that Foliot organised and led in London on 24 June.

[85] By the end of 1166, Foliot managed to resign his custody of the confiscated Canterbury benefices, something he had been attempting to do for some time, thus removing one source of conflict between him and Becket.

As the legates had no mandate to compel Becket to accept them as judges, the negotiations came to an end with the king and bishops still appealing to the papacy.

[87] On 13 April 1169, Becket excommunicated Foliot, along with Hugh, Earl of Norfolk, Josceline de Bohun, and seven royal officials.

Foliot then prepared to appeal his sentence to the pope in person, and travelled to Normandy in late June or early July, where he met the king, but proceeded no further towards Rome, as the papacy was attempting once more to secure a negotiated settlement.

[91] Foliot then proceeded to Rome, but at Milan he received word that his envoy at the papal court had secured the right for him to be absolved by Rotrou, Archbishop of Rouen.

When they did so, the royal anger at the timing of the excommunications was such that it led to Henry uttering the question often attributed to him "Will no one rid me of the turbulent priest".

[105] After the pope absolved Foliot's excommunication in early 1170, Becket exclaimed to a cardinal that "Satan is unloosed for the destruction of the Church".

"[120] The sermon so inspired Peter that he wrote a work entitled Pantheologus, which dealt with the distinctio method of exegesis, which was developing around this time.

[121][i] All of Foliot's surviving theological works are based on exegesis,[15] and may include nine sermons on the subject of Saints Peter and Paul, which were dedicated to Aelred of Rivaulx.

Leland also listed another work by Foliot, the Omeliae Gileberti, episcopi Herefordensis, which he stated was held at Forde Abbey.

[123] The medieval chronicler Walter Map praised him as "a man most accomplished in the three languages, Latin, French and English, and eloquent and clear in each of them".