Dictionary entry

ἐπιδιατάσσομαι

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

*† ἐπι-δια-τάσσομαι

to add provisions to a document: Ga 3:15 (cf. ἐπιδιαθήκη, a second will, F1J, BJ, ii, 2, 3; the word is used of wills in π., cf. Deiss., LAE, 87).†