A.T. Robertson Commentary Ephesians 6:2

"Honor thy father and mother (which is the first commandment with promise)," — Ephesians 6:2 (ASV)

Which (ητις). "Which very" = "for such is."

The first commandment with promise (εντολη πρωτη εν επαγγελια). Εν here means "accompanied by" (Alford). But why "with a promise"? The second has a general promise, but the fifth alone (Exodus 20:12) has a specific promise. Perhaps that is the idea. Some take it to be first because in the order of time it was taught first to children, but the addition of εν επαγγελια here to πρωτη points to the other view.