The verses 7:53 to 8:11 are not in the earliest manuscripts, but have been added later, maybe as late as around 1100 A.D. The stylistic differences hint at not being written by the apostle John. They did however exist as a separate document from the first century, and were added to complete Jesus dialogue at the feast of Tabernacles. The verses could have been placed elsewhere, since they break up Jesus dialogue at the Temple. However, they were at some time accepted as inspired and are included in most manuscripts (Textus Receptus).
Richard Blanchard (1925-2004)