60 Grk “Now it happened that when.” The introductory phrase ἐγένετο (egeneto, “it happened that”), common in Luke (69 times) and Acts (54 times), is redundant in contemporary English and has not been translated.
61 Grk “and while Jesus was being baptized and praying.” The first of these participles has been translated as a finite verb to be more consistent with English style.
62 Or “the sky”; the Greek word οὐρανός (ouranos) may be translated “sky” or “heaven,” depending on the context. In this context, although the word is singular, the English plural “heavens” connotes the Greek better than the singular “heaven” would, for the singular does not normally refer to the sky.

In other versions

Now when all the people were baptized, and when Jesus also had been baptized and was praying, the heavens were opened,

When all the people were being baptized, Jesus was baptized too. And as he was praying, heaven was opened

When all the people were baptized, Jesus also was baptized. As he was praying, heaven opened,

One day when the crowds were being baptized, Jesus himself was baptized. As he was praying, the heavens opened,

Now it happened that when all the people were baptized, Jesus also was baptized, and while he was praying, heaven was opened,

Now when all the people were baptized, it came to pass, that Jesus also being baptized, and praying, the heaven was opened,

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