Vincent's NT Word Studies
3. Even as (kaqwv). An awkward construction, there being nothing to answer to kaqwv.To abide (prosmeinai). To continue on. The compound does not occur in Paul, but is found in Acts xi. 23; xiii. 43; xviii. 18.
When I went (poreuomenov). Better, was going, or was on my way. The participle cannot refer to Timothy.
Might'st charge (paraggeilhv) See on Acts i. 4. Very common in Luke and Acts, but not in Paul. In 1st Timothy alone five times.
Some (tisin) Note the indefinite designation of the errorists, and comp. verse 6; iv. 1; v. 15, 24; vi. 21. The expression is contemptuous. It is assumed that Timothy knows who they are. This is after the Pauline manner. See Gal. i. 7; ii. 12; 1 Cor. iv. 18; xv. 12; 2 Cor. iii. 1; Col. ii. 4, 8.
That they teach no other doctrine (mh eterodidaskalein). Better, not to teach a different doctrine. For eterov different, see on Gal. i. 6. The verb Past o . o LXX. o Class. The charge is not to teach anything contrary to the sound teaching (verse 10) or irreconcilable with it. Comp. Gal. i. 6; 2 Cor. xi. 4; Rom. xvi. 17.
Robertson's NT Word Studies
1:3 {As I exhorted} (kaqws parekalesa). There is an ellipse of the principal clause in verse #4 ({so do I now} not being in the Greek). {To tarry} (prosmeinai). First aorist active infinitive of prosmenw, old verb, attributed by Luke to Paul in #Ac 13:43. {That thou mightest charge} (hina paraggeileis). Subfinal clause with hina and the first aorist active subjunctive of paraggellw, old verb, to transmit a message along (para) from one to another. See #2Th 3:4,6,10. Lock considers this idiom here an elliptical imperative like #Eph 4:29; 5:33. {Certain men} (tisin). Dative case. Expressly vague (no names as in #1:20), though Paul doubtless has certain persons in Ephesus in mind. {Not to teach a different doctrine} (me heterodidaskalein). Earliest known use of this compound like kakodidaskalein of Clement of Rome. Only other N.T. example in #6:3. Eusebius has heterodidaskalos. Same idea in #Ga 1:6; 2Co 11:4; Ro 16:17. Perhaps coined by Paul.