Numbers 23:20

Behold, I have received commandment to bless: and he hath blessed; and I cannot reverse it.

Behold, I have received commandment to bless is part of Balaam's unwilling prophecy of blessing over Israel, beautiful in expression, spoken as his second parable to Balak at Zophim on top of Pisgah after burnt offerings and communing alone with the angel of God, in the most exalted strains of inspiration. It means Balaam had received commandment from God to bless Israel, God himself had blessed them, and Balaam could not reverse, withhold, or change that blessing into a curse. God's purpose toward Israel prevailed, and the blessing God gave could not be undone or replaced by a curse. God does not lie, break his word, or change his purpose, and will never be induced to alter his purpose concerning Israel or let the promised blessing be reversed.

Balaam was hired and allured with promise of rich rewards to curse Israel by enchantments and sacrifices, and as a corrupt, hypocritical gain-seeker his heart longed to pronounce evil for reward. But he was forbidden by the Spirit of God to speak evil and controlled and compelled by God's power to speak blessing instead. Balak led him, conducting him from one place to another and from one point to another, in the vain hope of inducing him to turn the blessing into a curse. Yet neither Balaam's magic nor Balak's repeated efforts could overturn God's blessing, and it was vain to hope to obtain a curse.

The irreversibility rests on God's character and on his protection, for no enchantment or curse spoken by a diviner, no curse, enchantment, divination, or magic could have the least influence upon a nation that has the protection of Omnipotence. So long as Israel remained loyal and obedient to God's law, with God's favor upon them and God with them, no power in earth or hell could prevail against them, for his almighty power was their protection as his chosen. The curse Balaam was not allowed to pronounce he afterward brought upon Israel by seducing them into sin, for when they transgressed God's commandments they separated themselves from him and were left to feel the power of the destroyer. Israel's deliverance from hostile powers by God's favor is an assurance of his protecting care for obedient, faithful people in every age.

The constrained blessing displayed God's goodness and mercy when the king of Moab called Balaam to curse Israel to accomplish their destruction. Compelled to proclaim Israel God's chosen, Balaam proclaimed the richest and most sublime blessings and God's almighty power her protection. This gave the Moabites and Midianites evidence upon evidence that the mighty Jehovah was the God they should serve, clear and distinct light from the throne of God itself, the last ray of light to a stiff-necked people who had set their wills in defiance of God's will. Balak's failure to move Balaam from blessing to curse illustrates the steadfastness later seen when Luther was pressed to retract, where neither human applause nor fear of man could shake his decision because he was sustained by divine power.