Numbers 23:26

But Balaam answered and said unto Balak, told not I thee
He appeals to him for his honesty and faithfulness, for honest and faithful he would be thought to be, both to God and man; that when he first met him, he plainly told him what he must expect: from him:

saying, all that the Lord speaketh, that I must do;
which was very true, he was obliged to do as he had bid him, and speak what he had said unto him, though it was sore against his will; he would fain both have spoken and done otherwise, if he might have been permitted.