Abu Umamah bin Sahl bin Hunayf (may Allah be pleased with him) said: A man fell ill until he was reduced to nothing but skin and bone. A slave-girl came to him to visit him in his illness, and he committed fornication with her. His chest became constricted because of this sin of his. When people came to visit him, he said: "Ask the Messenger of Allah (peace and blessings be upon him) for me: I have committed an unlawful act with a woman, so let him (peace and blessings be upon him) establish the prescribed punishment (hadd) upon me and purify me." They mentioned this to the Messenger of Allah (peace and blessings be upon him) and said: "If he were carried to you, his bones would break apart, and if he were flogged, he would die." He (peace and blessings be upon him) said: "Then take a branch with a hundred twigs and strike him with it a single time."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 5547