The blessed person and what holding fast looks like
A blessing is pronounced on the person who does what verse 1 commands and “holds it fast,” meaning he keeps a firm grip on this way of life. Two concrete signs are given: he guards the Sabbath from being treated as ordinary, and he restrains himself from doing evil. The verse connects blessing to sustained, practiced obedience rather than a momentary intention.
Unit 3 (vv. 1–2 together): Public justice, worship practice, and personal restraint
Taken together, the commands show a broad moral vision: fair dealings in society (“justice”), right conduct (“righteousness”), faithful time set apart for God (Sabbath), and refusal to participate in wrongdoing. The approaching divine action is presented as the reason these commitments matter urgently now.