Matthew 23:20

οὖν (oûn, G3767) — (adverbially) certainly, or (conjunctionally) accordingly ὀμνύω (omnýō, G3660) — to swear, i.e. take (or declare on) oath ἐν (en, G1722) — "in," at, (up-)on, by, etc. θυσιαστήριον (thysiastḗrion, G2379) — a place of sacrifice, i.e. an altar (special or genitive case, literal or figurative) αὐτός (autós, G846) — the reflexive pronoun self, used (alone or in the comparative G1438 (ἑαυτοῦ)) of the… καί (kaí, G2532) — and, also, even, so then, too, etc.; often used in connection (or composition) with other… πᾶς (pâs, G3956) — all, any, every, the whole ἐπάνω (epánō, G1883) — up above, i.e. over or on (of place, amount, rank, etc.)