πῶς ἡμεῖς ἐκφευξόμεθα τηλικαύτης ἀμελήσαντες σωτηρίας, ἥτις ἀρχὴν λαβοῦσα λαλεῖσθαι διὰ τοῦ κυρίου ὑπὸ τῶν ἀκουσάντων εἰς ἡμᾶς ἐβεβαιώθηHe specifies the σωτηρία he is talking about as τηλικαύτη, then refers to its origin. Its origin reinforces its greatness, because it was first spoken (ἀρχὴν λαβοῦσα λαλεῖσθαι) by the Lord. But he does not say so quite that simply. The author's way is both terser and more elegant at the same time.
Note the three prepositional phrases he employs, bang-bang-bang. This great salvation was:
- First spoken διὰ τοῦ κυρίου
- Then confirmed ὑπὸ τῶν ἀκουσάντων
- εἰς ἡμᾶς
Over-woodenly, it would be something like this: "how shall we escape, after disregarding salvation so great as this, which having first been spoken by the Lord, unto us by those who heard was confirmed."