στήκω late Pres. formed from perf. ἕστηκα (see B1. § 17; WH, App. 169; Kennedy, Sources, 158; M, Pr. 238; MM, xxiii),

[in LXX: Exo.14:13 A, Jdg.16:26 B, 3Ki.8:11 B * ;]

= ἵστημι, to stand: Mrk.3:31 11:25, Jhn.1:26, Rev.12:4 (ἕστηκεν T). Metaphorical, to stand firm, stand fast: absol. Gal.5:1 (but see Field, Notes, 189 f.), 2Th.2:15; before ἐν, Jhn.8:44 (ἕστηκεν, T, R, mg.), 1Co.16:13, Php.1:27 4:1; with dative, Rom.14:4.†

(AS)

to stand; to stand firm, stand fast