Balaam could hardly await the morning, rejoicing no less than Balak's messengers at God's consent to his journey to Balak, and still hoping that he might succeed in bringing disaster upon Israel. In his haste to set out, he himself saddled his ass although he did not lack servants, whereupon God said: "O thou villain, their ancestor Abraham forestalled thee, for he too rose up early in the morning and in person saddled his ass to lead Isaac to sacrifice in fulfillment of the command that had reached him." 
The ass that Balaam took with him had been created on the sixth day of the creation. He had received it as a gift from Jacob, that he might not give evil counsel to Pharaoh concerning Jacob's children. It was upon his advice, nevertheless, that Pharaoh forced the Israelites to make bricks.  He took his two sons, Jannes and Jambres,  for it behooves a noble man always to have at least two companions upon any journey that he undertakes. 
Although God had now granted him permission to go on the journey, still His wrath was kindled when he set out. God said, "Behold, this man! He knows that I read each man's heart, and knows also that he departeth only to curse Israel."  This wickedness on his part had the result that even the Angel of Mercy turned against him as an enemy, standing in his way. At first the ass alone perceived the angel, and not Balaam, for God has so arranged it that human beings may not perceive the angels that surround them or else they would through terror lose their reason.  The ass, on the other hand, instantly perceived the angel. He at first stood in her way as she was in the middle of the road, so that she could turn aside on both sides; then she perceived him when the road narrowed, and she could turn to one side only; and finally she reached a spot where there was no road at all to which she could turn either on this side or on that. This was to teach Balaam the following lesson: if he wished to curse Abraham's children, he should have leeway on both sides, Ishmael's children and Keturah's children; if he wanted to curse Isaac's children, one side would still be open to him, Esau's children; but if he wanted to curse Jacob's children, he should never bring it to pass, for they are protected on both sides, on the one hand by Abraham and Isaac, on the other by Jacob and Levi, while God watches over them from above. "The wall on this side, and on that side," through which place he had to pass, were furthermore to indicate to him that he could not become master over Israel, who have in their possession the tables of the law, "that were written on both their sides." When the ass reached the wall that Jacob and Laban had erected as a token that they "would never pass over it for harm," she thrust her feet against it, to punish him for having broken his agreement with Jacob. 
Balaam, who had with blows attempted to make the ass walk straight ahead, flew into a rage when she lay down altogether and would not budge from the spot, so that he smote her all the more. Then the Lord opened the mouth of the ass, and permitted her to use speech, a gift that she had possessed ever since her creation, but had not until then used.  She said, "What have I done unto thee, that thou has smitten me these three times?" The first words of the ass were so chosen as to call Balaam's attention to the wickedness and uselessness of his undertaking against Israel; "Three times" was to remind him that he wished to curse a nation that "three times" in every year arranged pilgrimages to the Lord. The ass's speech was altogether to serve as a warning to Balaam to beware of his mouth, and not to curse Israel. The ass, through her speaking, was to instruct him that the mouth and the tongue are in God's hand.
Balaam answered the ass in the language in which she had addressed him, in Hebrew, which he did not, however, speak fluently. He said, "Because thou hast mocked me: I would there were a sword in mine hand, for now I had killed thee." The ass thereupon replied, "Thou canst not kill me save with a sword in thy hand; how then wilt thou destroy an entire nation with thy mouth!" Balaam was silent, knowing no reply.  The ass did not only make him ridiculous in the eyes of the elders of Moab that accompanied him, but she also exposed him as a liar. For when the ambassadors asked him why he had not chosen a horse rather than an ass for his journey, he answered that his saddle horse was in the pasture. Then the ass interrupted him, saying, "Am not I thine ass upon which thou hast ridden all thy life long?" Balaam: "I use thee as a beast of burden, but not for the saddle." The ass: "Nay, upon me has thou ridden since thine earliest day, and thou hast always treated me with as much affection as a man treats his wife." Balaam had now to admit that the ass had spoken the truth. 
Balak's princes were much amazed at this extraordinary miracle, but the ass died the moment she had spoken what she had to say. God did this for two reasons, firstly because He feared that the heathens might worship this ass were she to stay alive; and secondly because God wanted to spare Balaam the disgrace of having people point to his ass and say, "This is she that worsted Balaam." By this action it can be seen how highly God prizes the honor or pious men, if He even sought to spare the honor of this villain. It is out of consideration to mankind, also, that God has closed the mouth of animals, for were they to speak, man could not well use them for his service, since the ass, the most stupid of all animals, when she spoke, confounded Balaam, the wisest of the wise.