Israel was holiness unto the LORD, and the firstfruits of his increase: all that devour him shall offend; evil shall come upon them, saith the LORD. Israel was holiness unto the Lord - Fully consecrated to his service.
The first fruits of his increase - They were as wholly the Lord's, as the first fruits were the property of the priests according to the law Numbers 18:13. These the priests alone had a right to devote to their own use.
All that devour him shall offend - As they were betrothed to the Lord, they were considered his especial property; they therefore who injured them were considered as laying violent hands on the property of God. They who persecute God's children have a grievous burden to bear, an awful account to give.