Crowley refused and told Aziraphale that "we could have been us", before passionately kissing him. Following the kiss, Aziraphale told Crowley that he "forgives him".
Fans have talked about this moment non-stop since it aired, but one person whose thoughts we hadn't yet got were Tennant's himself - until now.
In a Q&A answering reader questions for The Guardian, Tennant was asked what it was like kissing Sheen for the scene, and who enjoyed it more.
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He responded: "Who enjoyed it the most? Presumably Michael was thrilled. How could he not be?
"But it was another day at work. The most difficult bit was other people’s awkwardness. We thought it was quite fun, so it was fine. He’d brushed his teeth."
Of course, season 3 has now been confirmed by Prime Video, so there could well be some more scenes of a similar nature on the way...
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Speaking on the show being renewed for season 3, creator Neil Gaiman, who also co-wrote the book on which the series has been based with the late Terry Pratchett, said: "I'm so happy finally to be able to finish the story Terry and I plotted in 1989 and in 2006.
"Terry was determined that if we made Good Omens for television, we could take the story all the way to the end.
"Season 1 was all about averting armageddon, dangerous prophecies, and the end of the world. Season 2 was sweet and gentle, although it may have ended less joyfully than a certain angel and demon might have hoped.
"Now in season 3, we will deal once more with the end of the world. The plans for armageddon are going wrong. Only Crowley and Aziraphale working together can hope to put it right. And they aren't talking."
Good Omens seasons 1-2 are available to stream now on Prime Video – try Amazon Prime Video for free for 30 days. Plus, read our guides to the best Amazon Prime series and the best movies on Amazon Prime.
Check out more of our Fantasy coverage or visit our TV Guide and Streaming Guide to find out what's on.
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