The blessed and the dogs
Whether the text reads 'wash their robes' or 'do his commandments', and what the difference carries.
Revelation 22:14-15
14Blessed are those who do his commandments, that they may have the right to the tree of life, and may enter in by the gates into the city.
15Outside are the dogs, the sorcerers, the sexually immoral, the murderers, the idolaters, and everyone who loves and practices falsehood.
What each tradition says
Rabbinic / Midrashic
No sourced position found. Checked the Jewish Encyclopedia art. "Revelation, Book of" (id 12712) in full — it treats the book's Jewish-apocalyptic strata but says nothing on Apoc. xxii. 14 or its two readings; no other Jewish Encyclopedia article (Revelation; Bible Canon) bears on the verse's Greek text, and Revelation stands outside the Jewish canon, so the public-domain rabinic corpus does not expound its individual readings.
Patristic
Tertullian cites Revelation as blessing those who act according to the precepts, so they may have power over the tree of life and over the gates, for entering the holy city. By contrast, dogs, sorcerers, fornicators, and murderers are out.
Tertullian, On Modesty (Ante-Nicene Fathers, vol. 4; trans. S. Thelwall) — Ch. XIX — Objections from the Revelation and the First Epistle of St. John Refuted
Catholic
The verse pronounces blessed those who wash their robes in the blood of the Lamb. This washing is so that they may have a right to the tree of life.
Douay-Rheims Bible (Challoner revision), The New Testament of our Lord and Saviour Jesus Christ, translated from the Latin Vulgate (Douay-Rheims) — Apoc. xxii. 14 (the verse as the Vulgate reads it)
Orthodox
No sourced position found. Checked CCEL ANF/NPNF (Victorinus on the Apocalypse is Western; no Greek commentary translated there), archive.org search for a public-domain English Andrew of Caesarea/Oecumenius on the Apocalypse (Andrew = modern translation; Hoskier's 1928 Oecumenius is the Greek text only), pravoslavieto.com (Philaret's Catechism; Synod of Jerusalem 1899 — nothing on Apoc. xxii. 14).
Reformed / Protestant
Gill notes that the Alexandrian copy, Ethiopic version, and Vulgate Latin read "wash their garments," with the Vulgate adding "in the blood of the Lamb," agreeing with Revelation 7:13. He says those whose persons and garments are washed in Christ's blood are truly blessed: justified, pardoned, and accepted with their services.
John Gill, John Gill's Exposition of the Whole Bible — On Revelation 22:14 (the two readings of the verse)
Evangelical
Wesley says those who do his commandments are happy; “his” refers to Christ, who says, “I come.” Through his gracious covenant they have right to the tree of life, meaning all the blessings it signifies. When Adam broke his commandment, he was driven from it.
John Wesley, John Wesley's Notes on the Bible — Notes on Revelation 22:14