Matthew 3:11μὲν
I baptize you with water for repentance, but after me will come One more powerful than I, whose sandals I am not worthy to carry. He will baptize you with the Holy Spirit and with fire.
Luke 3:16μὲν
John answered all of them: “I baptize you with water, but One more powerful than I will come, the straps of whose sandals I am not worthy to untie. He will baptize you with the Holy Spirit and with fire.
Acts 1:1μὲν
In my first book, O Theophilus, I wrote about all that Jesus began to do and to teach,
Romans 1:8μὲν
First, I thank my God through Jesus Christ for all of you, because your faith is being proclaimed all over the world.
1 Corinthians 1:12μέν
What I mean is this: Individuals among you are saying, “I follow Paul,” “I follow Apollos,” “I follow Cephas,” or “I follow Christ.”
Hebrews 1:7μὲν
Now about the angels He says: “He makes His angels winds, His servants flames of fire.”

Abbott-Smith

μέν,
conjunctive particle (originally a form of μήν), usually related to a following δέ or other adversative conjunction, and distinguishing the word or clause with which it stands from that which follows.
It is generally untranslatable and is not nearly so frequent in NT as in cl. Like δέ, it never stands first in a clause.

1. Answered by δέ or some other particle: μὲν . . . δέ, indeed . . . but, Mat.3:11, Luk.3:16, al.; with pronouns, ὃς μὲν . . . ὃς δέ, one . . . another, Mat.21:35, al.; pl., Php.1:16, 17; ὃ μὲν . . . ὃ δὲ . . . ὃ δέ, some . . . some . . . some, Mat.13:8; τοῦτο μὲν . . . τοῦτο δέ, partly . . . partly, Heb.10:33; μὲν . . . ἔπειτα, Jhn.11:6; μὲν . . . καί, Luk.8:5.

2. μέν solitarium, answered by no other particle: πρῶτον μέν (Bl., l.with), Rom.1:8 3:2, 1Co.11:18; μὲν οὖν in narrative, summing up what precedes or introducing something further (Bl., §78, 5), so then, rather, nay rather: Luk.11:28 (WH, μενοῦν), Act.1:6 9:31, al.; μὲν οὖν γε (Php.3:8, WH): see: μενοῦνγε.
(AS)

Sources: Abbott-Smith’s Manual Greek Lexicon of the New Testament (1922, public domain) and glosses from STEPBible TBESG (CC BY 4.0); STEPBible TAGNT (Greek New Testament, CC BY 4.0); the Berean Standard Bible (public domain). Reformatted by Word Study, wording unchanged. All sources and licenses.