Perhaps this Greek grammar rule was known much earlier since Theodore Beza seems to have known it. Several of the pre-1611 English Bibles seem to have followed this grammar rule at 2 Peter 1:1.The preserved text renders Titus 2:13 and 2 Peter 1:1 in a way that is consistent with the broader testimony of Scripture concerning the deity of Christ. The deity of Christ does not stand or fall on a grammatical rule formulated in the eighteenth century.
At Titus 2:13, the NKJV, the MKJV, and several other English translations read "our great God and Savior Jesus Christ,” more clearly presenting the deity of Christ. John Wesley translated it as “the great God, even our Saviour Jesus Christ.” Joseph Benson observed that Theodore Beza maintained “that one person only is spoken of, namely, Jesus Christ” (New Testament, II, p. 472). Granville Sharp noted that Beza “insists, however, that these two titles do not refer to two distinct persons, because the article is omitted before the second” (Remarks, p. 22).
Several pre-1611 English Bibles and many post-1611 English Bibles clearly, precisely, and accurately identify Jesus Christ as "our God and Saviour" at 2 Peter 1:1. William Tyndale in 1534, Miles Coverdale in 1535, and John Rogers in 1537 translated the last part of this verse as "righteousness that cometh of our God and Saviour Jesus Christ." In his 1538 Latin-English New Testament, Miles Coverdale rendered it “righteousness of our God and Saviour Jesus Christ.” The 1539 Great Bible, 1557 Whittingham's New Testament, 1560 Geneva Bible, 1568 Bishops' Bible, 1576 Tomson’s New Testament, 1657 Haak’s English translation of the Dutch Bible, 1755 Wesley's New Testament, 1842 Baptist or Bernard's, 1862 Young’s Literal Translation, 1866 American Bible Union Version, 1982 NKJV, 1994 Majority Text Interlinear, and other English translations render it "righteousness of our God and Saviour [or Savior] Jesus Christ." Thomas Goodwin maintained that “[Theodore] Beza reads it, ‘our God and our Saviour Jesus Christ,’” and that “it clearly meant one person, viz. Christ” (Works, VIII, p. 283).
At 2 Peter 1:1, the 2005 Cambridge edition of the KJV has this note taken from the standard 1762 Cambridge edition: “Gr. of our God and Saviour.” KJV editions printed at Oxford in 1810, 1821, 1835, 1857, 1865, 1868, and 1885, and at Cambridge in 1769, 1844, 1872, and 1887 also have this same note indicating the accurate translation and meaning of the Greek. An earlier KJV edition printed in London in 1711 had the same note and a cross reference to Titus 2:13. Granville Sharp observed: “In the margin of our present version the proper reading is ‘of our God and Saviour,‘ manifestly referring both titles to one person” (Remarks, p. 22). Concerning 2 Peter 1:1 in the Westminster Annotations printed in 1645, this note was also given: “Gr. Of our God and Saviour Jesus Christ.” Thus, the Bible scholars at the Westminster Assembly agreed with the pre-1611 English Bible translators and the editors of some standard KJV editions. Concerning 2 Peter 1:1 in a sermon printed in 1722, Edmund Calamy maintained that “the very construction of the words seems plainly to intimate that Jesus Christ is our God, as well as our Saviour” (Thirteen Sermons, p. 41).