ἀρχή, -ῆς, ἡ, [from Homer down], in the Sept. mostly equivalent to רֹאשׁ, רֵאֹשִׁית, תְּחִלָּה;
1. beginning, origin;
a. used absolutely, of the beginning of all things: ἐν ἀρχῇ, John 1:1f (Genesis 1:1); ἀπ’ ἀρχῆς, Matthew 19:4 (with which cf. Xenophon, mem. 1, 4, 5 ὁ ἐξ ἀρχῆς ποιῶν ἀνθρώπους), Matthew 19:8; John 8:44; 1 John 1:1; 1 John 2:13; 1 John 3:8; more fully ἀπ’ ἀρχῆς κτίσεως or κόσμου, Matthew 24:21; Mark 10:6; Mark 13:19; 2 Thessalonians 2:13 (where L [Tr marginal reading WH marginal reading] ἀπαρχήν, which see); 2 Peter 3:4; κατ’ ἀρχάς, Hebrews 1:10 (Psalm 101:26 (Ps. 102:26)).
b. in a relative sense, of the beginning of the thing spoken of: ἐξ ἀρχῆς, from the time when Jesus gathered disciples, John 6:64; John 16:4; ἀπ’ ἀρχῆς, John 15:27 (since I appeared in public); as soon as instruction was imparted, [1 John 2:7], 1 John 2:24; 1 John 3:11; 2 John 1:5f; more fully ἐν ἀρχῇ τοῦ εὐαγγελίου, Philippians 4:15 (Clement of Rome, 1 Cor. 47, 2 [see note in Gebh. and Harn. at the passage and cf.] Polycarp, ad Philipp. 11, 3); from the beginning of the gospel history, Luke 1:2; from the commencement of life, Acts 26:4; ἐν ἀρχῇ, in the beginning, when the church was founded, Acts 11:15. The accusative ἀρχήν [cf. Winers Grammar, 124 (118); Bp. Lightfoot on Colossians 1:18] and τὴν ἀρχήν in the Greek writings (cf. Lennep ad Phalarid., pp. 82ff and, p. 94ff, Lipsius edition; Brückner in DeWette's Handbook on John, p. 151) is often used adverbially, equivalent to ὅλως altogether, (properly, an accusative of 'direction towards': usque ad initium, [cf. Winers Grammar, 230 (216); Buttmann, 153 (134)]), commonly followed by a negative, but not always [cf. e. g. Dio Cassius fragment 101 (93 Dindorf); 45:34 (Dindorf vol. ii., p. 194); 59:20; 62:4; see, further, Lycurgus, § 125, Mätzner edition]; hence, that extremely difficult passage, John 8:25 τὴν... ὑμῖν, must in my opinion be interpreted as follows: I am altogether or wholly (i. e. in all respects, precisely) that which I even speak to you (I not only am, but also declare to you what I am; therefore you have no need to question me), [cf. Winers Grammar, 464 (432); Buttmann, 253 (218)]. ἀρχὴν λαμβάνειν, to take beginning, to begin, Hebrews 2:3. with the addition of the genitive of the thing spoken of: ὠδίνων, Matthew 24:8; Mark 13:8 (Mark 13:9) [(here R G plural); τῶν σημείων, John 2:11]; ἡμερῶν, Hebrews 7:3; τοῦ εὐαγγελίου, that from which the gospel history took its beginning, Mark 1:1; τῆς ὑποστάσεως, the confidence with which we have made a beginning, opposed to μέχρι τέλους, Hebrews 3:14. τὰ στοιχεῖα τῆς ἀρχῆς, Hebrews 5:12 (τῆς ἀρχῆς is added for greater explicitness, as in Latin rudimenta prima, Livy 1, 3; Justin., hist. 7, 5; and prima elamenta, Horat. sat. 1, 1, 26, etc.); ὁ τῆς ἀρχῆς τοῦ Χριστοῦ λόγος equivalent to ὁ τοῦ Χριστοῦ λόγος ὁ τῆς ἀρχῆς, i. e. the instruction concerning Christ such as it was at the very outset [cf. Winers Grammar, 188 (177); Buttmann, 155 (136)], Hebrews 6:1.
2. the person or thing that commences, the first person or thing in a series, the leader: Colossians 1:18; Revelation 1:8 Rec.; Rev 21:6; 22:13; (Deuteronomy 21:17; Job 40:14 (Job 40:19), etc.).
3. that by which anything begins to be, the origin, active cause (a sense in which the philosopher Anaximander, 8th century B.C., is said to have been the first to use the word; cf. Simplicius, on Aristotle, phys. f. 9, p. 326, Brandis edition and 32, p. 334, Brandis edition [cf. Teichmüller, Stud. zur Gesch. d. Begriffe, pp. 48ff 560ff]): ἡ ἀρχὴ τῆς κτίσεως, of Christ as the divine λόγος, Revelation 3:14 (cf. Düsterdieck at the passage; Clement of Alexandria, protrept. 1, p. 6, Potter edition [p. 30 edition Sylb.] ὁ λόγος ἀρχὴ θεῖα τῶν πάντων; in Evang. Nicod. c. 23 [p. 308, Tdf. edition, p. 736, Thilo edition] the devil is called ἡ ἀρχὴ τοῦ θανάτου καὶ ῥίζα τῆς ἁμαρτίας).
4. the extremity of a thing: of the corners of a sail, Acts 10:11; Acts 11:5; (Herodotus 4, 60; Diodorus 1, 35; others.).
5. the first place, principality, rule, magistracy [cf. English 'authorities'], (ἄρχω τινός): Luke 12:11; Luke 20:20; Titus 3:1; office given in charge (Genesis 40:13, 21; 2 Macc. 4:10, etc.), Jude 1:6. Hence the term is transferred by Paul to angels and demons holding dominions entrusted to them in the order of things (see ἄγγελος, 2 [cf. Bp. Lightfoot on Colossians 1:16; Meyer on Ephesians 1:21]): Romans 8:38; 1 Corinthians 15:24; Ephesians 1:21; Ephesians 3:10; Ephesians 6:12; Colossians 1:16; Colossians 2:10, 15. See ἐξουσία, 4 c. ββ.

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ἄρχι, (from ἄρχω, ἀρχός), an inseparable prefix, usually to names of office or dignity, to designate the one who is placed over the rest that hold the office (German Ober-, Erz-, [English arch- (chief-, high-)]), as ἀρχάγγελος, ἀρχιποίμην [which see], ἀρχιερεύς, ἀρχίατρος, ἀρχιευνοῦχος, ἀρχυπερέτης (in Egyptian inscriptions), etc., most of which belong to Alexandrian and Byzantine Greek. Cf. Thiersch, De Pentateuchi versione Alex. p. 77f.