Please note that most doctors have a modified version of the oath.
The origination of the oath have unknown. but many scholars think it was made by Hippocrates of Kos (The Father of Medicine) or one of his students.
Today and the oath.
The oath is still used by some med-schools. some doctors use other oaths. but mostly The Hippocratic Oath has been changed over the years. when it was wrote back in ancient Greece. During Nazi Germany, the government disallow them to use The Hippocratic Oath. But they still understood the rule of "Do No Harm" .
The Hippocratic oath (original)
"I swear by Apollo the physician, and Aesculapius the surgeon, likewise Hygeia and Panacea, and call all the gods and goddesses to witness, that I will observe and keep this underwritten oath, to the utmost of my power and judgment.
I will reverence my master who taught me the art. Equally with my parents, will I allow him things necessary for his support, and will consider his sons as brothers. I will teach them my art without reward or agreement; and I will impart all my acquirement, instructions, and whatever I know, to my master's children, as to my own; and likewise to all my pupils, who shall bind and tie themselves by a professional oath, but to none else.
With regard to healing the sick, I will devise and order for them the best diet, according to my judgment and means; and I will take care that they suffer no hurt or damage.
Nor shall any man's entreaty prevail upon me to administer poison to anyone; neither will I counsel any man to do so. Moreover, I will get no sort of medicine to any pregnant woman, with a view to destroy the child.
Further, I will comport myself and use my knowledge in a godly manner.
I will not cut for the stone, but will commit that affair entirely to the surgeons.
Whatsoever house I may enter, my visit shall be for the convenience and advantage of the patient; and I will willingly refrain from doing any injury or wrong from falsehood, and (in an especial manner) from acts of an amorous nature, whatever may be the rank of those who it may be my duty to cure, whether mistress or servant, bond or free.
Whatever, in the course of my practice, I may see or hear (even when not invited), whatever I may happen to obtain knowledge of, if it be not proper to repeat it, I will keep sacred and secret within my own breast.
If I faithfully observe this oath, may I thrive and prosper in my fortune and profession, and live in the estimation of posterity; or on breach thereof, may the reverse be my fate!["-http://en.wikipedia.org/wiki/Hippocratic_Oath"