"After being instructed by Kamsa, the demon Kesi assumed the form of a terrible horse. He entered the area of Vrndavana, his great mane flying and his hooves digging up the earth. He began to whinny and terrify the whole world. Krsna saw that the demon was terrifying all the residents of Vrndavana with his whinnying and his tail wheeling in the sky like a big cloud. Krsna could understand that the horse was challenging Him to fight. The Lord accepted his challenge and stood before the Kesi demon. As He called him to fight, the horse began to proceed towards Krsna, making a horrible sound like a roaring lion. Kesi rushed toward the Lord with great speed and tried to trample Him with his legs, which were strong, forceful and as hard as stone. Krsna, however, immediately caught hold of his legs and thus baffled him. Being somewhat angry, Krsna began to move around the horse dextrously. After a few rounds, He threw him a hundred yards away, just as Garuda throws a big snake. Thrown by Krsna, the horse immediately passed out, but after a little while he regained consciousness and with great anger and force rushed toward Krsna again, this time with his mouth open. As soon as Kesi reached Him, Krsna pushed His left hand within the horse's mouth. The horse felt great pain because the arm of Krsna felt to him like a hot iron rod. Immediately his teeth fell out. Krsna's hand within the mouth of the horse at once began to inflate, and Kesi's throat choked up. As the great horse began to suffocate, perspiration appeared on his body, and he threw his legs hither and thither. As his last breath came, his eyeballs bulged in their sockets, and he passed stool and urine simultaneously. Thus the vital force of his life expired. When the horse was dead, his mouth became loose and Krsna could extract His hand without difficulty. He did not feel any surprise that the Kesi demon was killed so easily, but the demigods were amazed, and out of their great appreciation they offered Krsna greetings by showering flowers."
Krnsa Book, Chapter 37
Bhaktivedanta Book Trust. Excerpted from text and purport of HDG A.C. Bhaktivedanta Swami Srila Prabhupada.