17 μου (mou, “my”) is found after ἀδελφοί (adelphoi) in a number of significant witnesses (א A B* D1 048 326 1175 2464 ), but lacking in most other witnesses (𝔓46 B2 D* F G Ψ 0243 33 1739 1881 𝔐 lat). Every other time Paul says “So then, brothers (and sisters)” he adds “my” (ὥστε, ἀδελφοί μου; hōste, adelphoi mou). There is no good reason why scribes would intentionally omit “my” here but not elsewhere. Thus, the longer reading is in conformity with Paul’s general style and as such seems to be scribally motivated. has the word in brackets, indicating doubt as to its authenticity. Grk “brothers.” See note on the phrase “brothers and sisters” in .
18 Grk “speaking in tongues.” The words “anyone from” are supplied for the sake of clarity.

In other versions

So, my brothers, earnestly desire to prophesy, and do not forbid speaking in tongues.

Therefore, my brothers and sisters, be eager to prophesy, and do not forbid speaking in tongues.

So then, my brothers and sisters, be eager to prophesy, and do not forbid speaking in tongues.

So, my dear brothers and sisters, be eager to prophesy, and don’t forbid speaking in tongues.

So then, my brothers, desire to prophesy, and do not prevent speaking with tongues.

Wherefore, brethren, covet to prophesy, and forbid not to speak with tongues.

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