William Flower, otherwise Branch, was born at Snow-hill, in the county of Cambridge, where he went to school some years, and then came to the abby of Ely. After he had remained a while he became a professed monk, was made a priest in the same house, and there celebrated and sang Mass. After that, by reason of a visitation, and certain injunctions by the authority of Henry VIII he took upon him the habit of a secular priest, and returned to Snow-hill, where he was born, and taught children about half a year.
He then went to Ludgate, in Suffolk, and served as a secular priest about a quarter of a year; from thence to Stoniland; at length to Tewksbury, where he married a wife, with whom he ever after faithfully and honestly continued. After marriage he resided at Tewksbury about two years, and thence went to Brosley, where he practiced physic and surgery; but departing from those parts he came to London, and finally settled at Lambeth, where he and his wife dwelt together. However, he was generally abroad, excepting once or twice in a month, to visit and see his wife. Being at home upon Easter Sunday morning, he came over the water from lambeth into St. Margaret's Church at Westminster; when seeing a priest, named John Celtham, administering and giving the Sacrament of the alter to the people, and being greatly offended in his conscience with the priest for the same, he struck and wounded him upon the head, and also upon the arm and hand, with his wood knife, the priest having at the same time in his hand a chalice with the consecrated host therein, which became sprinkled with blood.
Mr. Flower, for this injudicious zeal, was heavily ironed, and put into the gatehouse at Westminster; and afterward summoned before bishop Bonner and his ordinary, where the bishop, after he had sworn him upon a Book, ministered articles and interrogatories to him.
After examination, the bishop began to exhort him again to return to the unity of his mother the Catholic Church, with many fair promises. These Mr. Flower steadfastly rejecting, the bishop ordered him to appear in the same place in the afternoon, and in the meantime to consider well his former answer; but he, neither apologizing for having struck the priest, nor swerving from his faith, the bishop assigned him the next day, April 20, to receive sentence if he would not recant. The next morning, the bishop accordingly proceeded to the sentence, condemning and excommunicating him for a heretic, and after pronouncing him to be degraded, committed him to the secular power.
On April 24, St. Mark's eve, he was brought to the place of martyrdom, in St. Margaret's churchyard, Westminster, where the fact was committed: and there coming to the stake, he prayed to Almighty God, made a confession of his faith, and forgave all the world.
This done, his hand was held up against the stake, and struck off, his left hand being fastened behind him. Fire was then set to him, and he burning therein, cried with a loud voice, "O Thou Son of God receive my soul!" three times. His speech being now taken from him, he spoke no more, but notwithstanding he lifted up the stump with his other arm as long as he could.
Thus he endured the extremity of the fire, and was cruelly tortured, for the few fagots that were brought being insufficient to burn him they were compelled to strike him down into the fire, where lying along upon the ground, his lower part was consumed in the fire, whilst his upper part was little injured, his tongue moving in his mouth for a considerable time.