Dictionary entry

διατηρέω

G. Abbott-Smith's A Manual Greek Lexicon of the New Testament with Strong's

δια-τηρέω, -ῶ

[in LXX for שׁמר, נצר, etc.; seq. ἀπό (for מִן), as in Ps 11 (12):8;]

to keep carefully: Lk 2:51; seq. ἐκ, Ac 15:29.†