Numbers 22:14-18

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.

And they came to Balaam, and said to him, Thus saith Balak the son of Zippor, Let nothing, I pray thee, hinder thee from coming unto me:

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.