▼ The word עַד (’ad, “until”) would give the reading “until he fills your mouth with laughter,” subordinating the verse to the preceding with some difficulty in interpretation. It would be saying that God will not reject the blameless man until he filled Job with joy. Almost all commentators and modern versions change the pointing to עוֹד (’od, “yet”), forming a hope for the future blessing of joy for Job.

▼ “Laughter” (and likewise “gladness”) will here be metonymies of effect or adjunct, being put in place of the reason for the joy – restoration.