Now if the fall of them be the riches of the world, and the diminishing of them the riches of the Gentiles; how much more their fulness?
Now if the fall of them ('their lapse') be the riches of the (Gentile) world - as being the occasion of their accession to Christ,
And the diminishing of them - that is, the reduction of the true Israel to so small a remnant;
The riches of the Gentiles; how much more their fullness! - their full recovery (see the note at Romans 11:26): q.d., 'If an event so untoward as Israel's fall was the occasion of such unspeakable good to the Gentile world, of how much greater good may we expect an event so blessed as their full recovery to be productive?'