I don't see why McGrath's comments on John 20:28 are a stretch. The idea that Jesus and his Father are the same God is what is untenable in the gospel of John in view of many verses such as 17:3 that make a clear distinction between the only true God and the one he sent forth.
This has nothing to do with the erroneous trinitarian notion of God and Jesus are the same God ( the trinity doesn't say that by the way, it says that God as God has made Himself Know to us, is a triune "entity") and since I am not a trinitarian, it has nothing to do with me.
This is about whether or not Jesus was worshiped in Revelation.
The use of the singular in Rev 22:3 clearly refers to God. Saying it refers to worship and service of the throne rather than God himself to explain away the singular is a stretched interpretation. If the author had wanted to say that both Jesus and God were worshipped and served in this verse he could easily have done so.
IF the singular referrs to God then John of Patmos is saying that God and Jesus ( the Lamp) are the same. note the wording:
The pronoun autos can mean Him, Her , the same, themselves, himself, etc.
And we have:
The River of Life
22 Then the angel a showed me the river of the water of life, bright as crystal, flowing from the throne of God and of the Lamb 2 through the middle of the street of the city. On either side of the river is the tree of life b with its twelve kinds of fruit, producing its fruit each month; and the leaves of the tree are for the healing of the nations. 3 Nothing accursed will be found there any more. But the throne of God and of the Lamb will be in it, and his servants c will worship him; 4 they will see his face, and his name will be on their foreheads. 5 And there will be no more night; they need no light of lamp or sun, for the Lord God will be their light, and they will reign forever and ever.
6 And he said to me, “These words are trustworthy and true, for the Lord, the God of the spirits of the prophets, has sent his angel to show his servants d what must soon take place.”
7 “See, I am coming soon! Blessed is the one who keeps the words of the prophecy of this book.”
Epilogue and Benediction
8 I, John, am the one who heard and saw these things. And when I heard and saw them, I fell down to worship at the feet of the angel who showed them to me; 9 but he said to me, “You must not do that! I am a fellow servant e with you and your comrades f the prophets, and with those who keep the words of this book. Worship God!”
10 And he said to me, “Do not seal up the words of the prophecy of this book, for the time is near. 11 Let the evildoer still do evil, and the filthy still be filthy, and the righteous still do right, and the holy still be holy.”
12 “See, I am coming soon; my reward is with me, to repay according to everyone’s work. 13 I am the Alpha and the Omega, the first and the last, the beginning and the end.”
14 Blessed are those who wash their robes, g so that they will have the right to the tree of life and may enter the city by the gates. 15 Outside are the dogs and sorcerers and fornicators and murderers and idolaters, and everyone who loves and practices falsehood.
16 “It is I, Jesus, who sent my angel to you with this testimony for the churches. I am the root and the descendant of David, the bright morning star.”
17 The Spirit and the bride say, “Come.”
And let everyone who hears say, “Come.”
And let everyone who is thirsty come.
Let anyone who wishes take the water of life as a gift.
18 I warn everyone who hears the words of the prophecy of this book: if anyone adds to them, God will add to that person the plagues described in this book; 19 if anyone takes away from the words of the book of this prophecy, God will take away that person’s share in the tree of life and in the holy city, which are described in this book.
20 The one who testifies to these things says, “Surely I am coming soon.”
Amen. Come, Lord Jesus!
21 The grace of the Lord Jesus be with all the saints. Amen. h
All of Chapter 22 is filled with "Jesus and God being one" implications.
But just looking at that begnning we have the mention of the thron of God AND the Lamp:
22 Then the angel a showed me the river of the water of life, bright as crystal, flowing from the throne of God and of the Lamb 2 through the middle of the street of the city. On either side of the river is the tree of life b with its twelve kinds of fruit, producing its fruit each month; and the leaves of the tree are for the healing of the nations. 3 Nothing accursed will be found there any more. But the throne of God and of the Lamb will be in it, and his servants c will worship him
We have "autos" translated as HIm and applying to BOTH God and the Lamb who are BOTh upon the Throne.
This is where the trinitarian will say "There you have it", but where I simply say that, As the Word and Son of God, Christ is worshipped WITH the Father.