Charles Ellicott Commentary Psalms 127:3

"Lo, children are a heritage of Jehovah; [And] the fruit of the womb is [his] reward." — Psalms 127:3 (ASV)

Children. —With the true patriarchal feeling of the blessing of a numerous offspring, the poet here directly alludes to Genesis 30:2. “Heritage of Jehovah” is, of course, “heritage from Jehovah,” i.e., a promise granted by Him, just as Israel itself was a possession He made for Himself.