A.T. Robertson Commentary Matthew 5:27

"Ye have heard that it was said, Thou shalt not commit adultery:" — Matthew 5:27 (ASV)

Thou shalt not commit adultery (ου μοιχευσεις). These quotations (verses 21,27,33) from the Decalogue (Exodus 20 and De 5) are from the Septuagint and use ου and the future indicative (volitive future, common Greek idiom). In 5:43 the positive form, volitive future, occurs (αγαπησεις). In 5:41 the third person (δοτω) singular second aorist active imperative is used. In 5:38 no verb occurs.