Joh or Joh. may refer to:
The First Epistle of John, often referred to as First John (US) or One John (UK) (and written 1 John) is a book of the New Testament. This fourth catholic or "general" epistle is attributed to John the Evangelist, traditionally thought to be the author of the Gospel of John and the other two Epistles of John. This Epistle was probably written in Ephesus between the years 95–110. The work was written to counter docetism, which is the belief that Jesus did not come "in the flesh", but only as a spirit. It also defined how Christians are to discern true teachers: by their ethics, their proclamation of Jesus in the flesh, and by their love.
The Epistle is traditionally held to have been composed by John the Evangelist, at Ephesus, when the writer was in advanced age. The epistle's content, language and conceptual style are very similar to the Gospel of John, 2 John, and 3 John, indicating that they were written by the same author. Indeed, at the end of the 19th century scholar Ernest DeWitt Burton wrote that there could be "no reasonable doubt" that 1 John and the gospel were written by the same author, and Amos Wilder has said that, "Early Christian tradition and the great majority of modern scholars have agreed on the common authorship of these writings, even where the author has not been identified with the apostle John."
The Second Epistle of John, often referred to as Second John and often written 2 John, is a book of the New Testament attributed to John the Evangelist, traditionally thought to be the author of the Gospel of John and the other two epistles of John.
The language of this epistle is remarkably similar to 3 John. It is therefore suggested by a few that a single author composed both of these letters. The traditional view contends that all the letters are by the hand of John the apostle, and the linguistic structure, special vocabulary, and polemical issues all lend toward this theory.
Also significant is the clear warning against paying heed to those who say that Jesus was not a flesh-and-blood figure: "For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh." This establishes that, from the time the epistle was first written, there were those who had docetic Christologies, believing that the human person of Jesus was actually pure spirit.