26 Grk “Now it happened that.” 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.
27 Grk “he”; the referent (Zechariah) has been specified in the translation for clarity.
28 Grk “serving as priest in the order of his division before God.” Zechariah’s division would be on duty twice a year for a week at a time.

In other versions

Now while he was serving as priest before God when his division was on duty,

Once when Zechariah’s division was on duty and he was serving as priest before God,

When his division was on duty and he was serving as priest before God,

One day Zechariah was serving God in the Temple, for his order was on duty that week.

And it happened that while he was serving as priest before God in the order of his division,

And it came to pass, that while he executed the priest’s office before God in the order of his course,

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