The Levites were Moses' closest kinsmen. Perhaps it was for this reason, as well as their loyalty to the Lord, that they sided with Moses. Their decision and obedience (v. 28) demonstrated their faith in God. They chose to go the way of His appointed leader, Moses, instead of following their rebellious brethren.
God's punishment of the rebels was severe (v. 27) because of the seriousness of their offense. It was also merciful; only 3,000 of the 600,000 men died (v. 28).
The Levites' blessing was God's choice of their tribe as the priestly tribe in Israel (Num. 3:12-13). The nation as a whole forfeited its right to be a kingdom of priests (19:6) by its rebellion here.
"The idiom fill the hands' [the literal meaning of "dedicate yourselves,"NASB, or "you have been set apart,"NIV, v. 29] means institute to a priestly office,' install,' inaugurate,' and the like."522
