This celebrated treatise relates to two texts in the Epistles of St. John and St. Paul. The first of these is in 1 John v. 7. “For there are three that bear record in heaven, the Father, the Son, and the Holy Ghost, and these three are one.” This text he considers as a gross corruption of Scripture, which had its origin among the Latins, who interpreted the Spirit, Water, and Blood to be the Father, Son, and Holy Ghost, in order to prove them one. With the same view Jerome inserted the Trinity in express words in his version. The Latins marked his variations in the margins of their books; and in the twelfth and following centuries, when the disputations of the schoolmen were at their height, the variation began to creep into the text in transcribing. After the invention of printing, it crept out of the Latin into the printed Greek, contrary to the authority of all the Greek manuscripts and ancient versions; and from the Venetian press it went soon after into Greece. After proving these positions Sir Isaac gives the following paraphrase of this remarkable passage, which is given in italics. “_Who is he that overcometh the world, but he that believeth that Jesus is the Son of God_, that Son spoken of in the Psalms, where he saith, ‘thou art my Son; this day have I begotten thee.’ _This is he that_, after the Jews had long expected him, came, first in a mortal body, _by_ baptism of _water_, and then in an immortal one, by shedding his _blood_ upon the cross and rising again from the dead; _not by water only, but by water and blood_; being the Son of God, as well by his resurrection from the dead (Acts xiii. 33), as by his supernatural birth of the virgin (Luke i. 35). _And it is the Spirit_ also _that_, together with the water and blood, _beareth witness_ of the truth of his coming; _because the Spirit is truth_; and so a fit and unexceptionable witness. _For there are three that bear record_ of his coming; _the Spirit_, which he promised to send, and which was since shed forth upon us in the form of cloven tongues, and in various gifts; _the_ baptism of _water_, wherein God testified ‘this is my beloved Son;’ _and the_ shedding of his _blood_, accompanied with his resurrection, whereby he became the most faithful martyr, or witness, of this truth. _And these three_, the spirit, the baptism, and passion of Christ, _agree in_ witnessing _one_ and the same thing (namely, that the Son of God is come); and, therefore, their evidence is strong: for the law requires but two consenting witnesses, and here we have three: _and if we receive the witness of men, the_ threefold _witness of God_, which he bare of his Son, by declaring at his baptism ‘this is my beloved Son,’ by raising him from the dead, and by pouring out his Spirit on us, _is greater_; and, therefore, ought to be more readily received.”