27 The word of the Lord is a technical expression in OT literature, often referring to a divine prophetic utterance (e.g., Gen 15:1, Isa 1:10, Jonah 1:1). In the NT it occurs 15 times: 3 times as ῥῆμα τοῦ κυρίου (rhēma tou kuriou; here and in Luke 22:61, 1 Pet 1:25) and 12 times as λόγος τοῦ κυρίου (logos tou kuriou; Acts 8:25; 13:44, 48, 49; 15:35, 36; 16:32; 19:10, 20; 1 Thess 1:8, 4:15; 2 Thess 3:1). As in the OT, this phrase focuses on the prophetic nature and divine origin of what has been said.
28 The imperfect verb ἔλεγεν (elegen) is taken as a customary imperfect.
29 John … Spirit. This remark repeats Acts 1:5.

In other versions

And I remembered the word of the Lord, how he said, ‘John baptized with water, but you will be baptized with the Holy Spirit.’

Then I remembered what the Lord had said: ‘John baptized with water, but you will be baptized with the Holy Spirit.’

I remembered the word of the Lord, how he said, ‘John baptized with water, but you will be baptized with the Holy Spirit.’

Then I thought of the Lord’s words when he said, ‘John baptized with water, but you will be baptized with the Holy Spirit.’

And I remembered the word of the Lord, how he said, ‘John baptized with water, but you will be baptized with the Holy Spirit.’

Then remembered I the word of the Lord, how that he said, John indeed baptized with water; but ye shall be baptized with the Holy Ghost.

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