Bede's Ecclesiastical History of England, ed. by A.M. Sellar, , at sacred-texts.com
AT that time, also, the East Saxons, at the instance of King Oswy, again received the faith, which they had formerly cast off when they expelled Mellitus, their bishop.For Sigbert,who reigned next to Sigbert surnamed The Little, was then king of that nation, and a friend to King Oswy, who, when Sigbert came to the province of the Northumbrians to visit him, as he often did, used to endeavour to convince him that those could not be gods that had been made by the hands of men; that a stock or a stone could not be proper matter to form a god, the residue whereof was either burned in the fire, or framed into any vessels for the use of men, or else was cast out as refuse, trampled on and turned into dust. That God is rather to be understood as incomprehensible in majesty and invisible to human eyes, almighty, eternal, the Creator of heaven and earth and of mankind; Who governs and will judge the world in righteousness, Whose eternal abode must be believed to be in Heaven, and not in base and perishable metal; and that it ought in reason to be concluded, that all those who learn and do the will of Him by Whom they were created, will receive from Him eternal rewards. King Oswy having often, with friendly counsel, like a brother, said this and much more to the like effect to King Sigbert, at length, aided by the consent of his friends, he believed, and after he had consulted with those about him, and exhorted them, when they all agreed and assented to the faith, he was baptized with them by Bishop Finan, in the king’s township above spoken of, which is called At the Wall,because it is close by the wall which the Romans formerly drew across the island of Britain, at the distance of twelve miles from the eastern sea.
King Sigbert, having now become a citizen of the eternal kingdom, returned to the seat of his temporal kingdom, requesting of King Oswy that he would give him some teachers, to convert his nation to the faith of Christ, and cleanse them in the fountain of salvation. Wherefore Oswy, sending into the province of the Midland Angles, summoned the man of God, Cedd, and, giving him another priest for his companion, sent them to preach the Word to the East Saxons. When these two, travelling to all parts of that country, had gathered a numerous Church to the Lord, it happened once that Cedd returned home, and came to the church of Lindisfarne to confer with Bishop Finan; who, finding that the work of the Gospel had prospered in his hands, made him bishop of the nation of the East Saxons, calling to him two other bishops to assist at the ordination. Cedd, having received the episcopal dignity, returned to his province, and pursuing the work he had begun with more ample authority, built churches in divers places, and ordained priests and deacons to assist him in the Word of faith, and the ministry of Baptism,especially in the city which, in the language of the Saxons, is called Ythancaestir,as also in that which is named Tilaburg. The first of these places is on the bank of the Pant, the other on the bank of the Thames. In these, gathering a flock of Christ’s servants, he taught them to observe the discipline of a rule of life, as far as those rude people were then capable of receiving it.
Whilst the teaching of the everlasting life was thus, for no small time, making daily increase in that province to the joy of the king and of all the people, it happened that the king, at the instigation of the enemy of all good men, was murdered by his own kindred. They were two brothers who did this wicked deed; and being asked what had moved them to it, they had nothing else to answer, but that they had been incensed against the king, and hated him, because he was too apt to spare his enemies, and calmly forgave the wrongs they had done him, upon their entreaty. Such was the crime for which the king was killed, because he observed the precepts of the Gospel with a devout heart; but in this innocent death his real offence was also punished, according to the prediction of the man of God. For one of those nobles that murdered him was unlawfully married, and when the bishop was not able to prevent or correct the sin, he excommunicated him, and commanded all that would give ear to him not to enter this man’s house, nor to eat of his meat. But the king made light of this command, and being invited by the noble, went to a banquet at his house. As he was going thence, the bishop met him. The king, beholding him, immediately dismounted from his horse, trembling, and fell down at his feet, begging pardon for his offence; for the bishop, who was likewise on horseback, had also alighted. Being much incensed, he touched the prostrate king with the rod he held in his hand, and spoke thus with the authority of his office:
"I tell thee, forasmuch as thou wouldest not refrain from the house of that sinful and condemned man, thou shalt die in that very house." Yet it is to be believed, that such a death of a religious man not only blotted out his offence, but even added to his merit; because it happened on account of his piety and his observance of the commands of Christ.
Sigbert was succeeded in the kingdom by Suidhelm, the son of Sexbald, who was baptized by the same Cedd, in the province of the East Angles, in the royal township, called Rendlaesham,’ that is, Rendil’s Dwelling; and Ethelwald,king of the East Angles, brother to Anna, king of the same people, received him as he came forth from the holy font.