The island is situated opposite the borders of the South Saxons and the Gewissae, being separated from it by a sea, three miles wide, which is called Solvente.(642) In this sea, the two tides of the ocean, which break upon Britain all round its coasts from the boundless northern ocean, daily meet in conflict beyond the mouth of the river Homelea,(643) which runs into the aforesaid sea, through the lands of the Jutes, belonging to the country of the Gewissae; and after this struggle of the tides, they fall back and return into the ocean whence they come. Chap. XVII. Of the Synod held in the plain of Haethfelth, Archbishop Theodore being president. [680 A.D.] About this time, Theodore being informed that the faith of the Church at Constantinople was much perplexed by the heresy of Eutyches,(644) and desiring that the Churches of the English, over which he presided, should remain free from all such taint, convened an assembly of venerable bishops and many learned men, and diligently inquired into the faith of each. He found them all of one mind in the Catholic faith, and this he caused to be committed to writing by the authority of the synod as a memorial, and for the instruction of succeeding generations; the beginning of which document is as follows: “In the name of our Lord and Saviour Jesus Christ, under the rule of our most pious lords, Egfrid, king of of the Northumbrians, in the tenth year of his reign, the seventeenth of September, the eighth indiction; Ethelred, king of the Mercians, in the sixth year of his reign; Aldwulf king of the East Angles, in the seventeenth year of his reign; and Hlothere, king of Kent, in the seventh year of his reign;(645) Theodore, by the grace of God, archbishop of the island of Britain, and of the city of Canterbury, being president, and the other venerable bishops of the island of Britain sitting with him, the holy Gospels being laid before them, at the place which, in the Saxon tongue, is called Haethfelth,(646) we conferred together, and set forth the right and orthodox faith, as our Lord Jesus Christ in the flesh delivered the same to His disciples, who beheld His Presence and heard His words, and as it is delivered by the creed of the holy fathers, and by all holy and universal synods in general, and by the consent of all approved doctors of the Catholic Church. We, therefore, following them, in piety and orthodoxy, and professing accordance with their divinely inspired doctrine, do believe agreeably to it, and with the holy fathers confess the Father, and Son, and Holy Ghost, to be properly and truly a Trinity consubstantial in Unity, and Unity in Trinity, that is, one God in three Subsistences or consubstantial persons, of equal glory and honour.”