Numbers 22:16 (KJV)

Behold, there is a people come out of Egypt, which covereth the face of the earth: come now, curse me them; peradventure I shall be able to overcome them, and drive them out.

And God said unto Balaam, Thou shalt not go with them; thou shalt not curse the people: for they are blessed.

And Balaam rose up in the morning, and said unto the princes of Balak, Get you into your land: for the LORD refuseth to give me leave to go with you.

And the princes of Moab rose up, and they went unto Balak, and said, Balaam refuseth to come with us.

And Balak sent yet again princes, more, and more honourable than they.

For I will promote thee unto very great honour, and I will do whatsoever thou sayest unto me: come therefore, I pray thee, curse me this people.

And Balaam answered and said unto the servants of Balak, If Balak would give me his house full of silver and gold, I cannot go beyond the word of the LORD my God, to do less or more.

Now therefore, I pray you, tarry ye also here this night, that I may know what the LORD will say unto me more.

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 Balaam rose up in the morning, and saddled his ass, and went with the princes of Moab.