Analysis of information sources in references of the Wikipedia article "雅各福音書" in Chinese language version.
But some say, basing it on a tradition in the Gospel according to Peter, as it is entitled, or "The Book of James," that the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honour of Mary in virginity to the end, so that that body of hers which was appointed to minister to the Word which said, "The Holy Ghost shall come upon thee and the power of the Most High shall overshadow thee," might not know intercourse with a man after that the Holy Ghost came into her and the power from on high overshadowed her. And I think it in harmony with reason that Jesus was the first-fruit among men of the purity which consists in chastity and Mary among women; for it were not pious to ascribe to any other than to her the first-fruit of virginity.
But some say, basing it on a tradition in the Gospel according to Peter, as it is entitled, or "The Book of James," that the brethren of Jesus were sons of Joseph by a former wife, whom he married before Mary. Now those who say so wish to preserve the honour of Mary in virginity to the end, so that that body of hers which was appointed to minister to the Word which said, "The Holy Ghost shall come upon thee and the power of the Most High shall overshadow thee," might not know intercourse with a man after that the Holy Ghost came into her and the power from on high overshadowed her. And I think it in harmony with reason that Jesus was the first-fruit among men of the purity which consists in chastity and Mary among women; for it were not pious to ascribe to any other than to her the first-fruit of virginity.