Numbers 22:20
And God came unto Balaam at night, and said unto him, If the men come to call thee, rise up, and go with them; but yet the word which I shall say unto thee, that shalt thou do. And God came unto Balaam at night, and said unto him, If the men come to call thee, rise up, and go with them; but yet the word which I shall say unto thee, that shalt thou do.
The verse belongs to Balaam's seeking counsel while still entertaining Balak's offer, when his duty was to refuse the reward and dismiss the messengers, yet he professed obedience to God while trying to comply with Balak's wishes. God came to him at night, speaking through an angel, after He had already told him not to go. The word given that night was conditional permission to rise and go with the men only if they came to call him, and even then to speak and do only what God commanded.
The permission was God suffering Balaam to follow his own inclination and determined course, because he was anxious for the privilege of going and had already chosen his course and sought God's sanction for it. It was an allowance granted to one trying to please both God and men, not approval of his choice or of his covetous motives. He was strongly drawn and eager for the promised reward, with covetousness and selfishness entering his heart and love of honor and gain striving for mastery. Fear of God's power held back his greed without conquering it, so that he would have gratified his covetousness if he had dared.
To go without the men's call was wrong and presumptuous, and Balaam's going in that manner brought God's anger. Even in going he was still strictly required to deliver exactly the message God gave him and not his own. Because he claimed to be God's prophet, his words would be treated as divinely authorized, so he was not free to speak as he pleased.
The permission does not make Balaam's choice a reliable example of divine guidance, for God may allow people to follow desires they persist in pursuing despite already knowing His will. His resulting experience did not prove that his desire or course was right, so relying on such an experience can deceive. In the wider account, Balak's conducting Balaam from one point to another in the vain hope of turning God's blessing of Israel into a curse fails completely. Human applause and fear of man are alike powerless to move one sustained by divine power to turn God's blessing into a curse.