“ Without this tradition, it would be impossible to fully understand the written Torah. In some cases, the Oral Torah overturns the literal meaning of verses in the written Torah (one famous example being "an eye for an eye" of Exodus 21:23-25) .
This tradition was passed down from the time of the Exodus until around 200 CE. At that time, Roman persecution threatened the chain of tradition, and Rabbi Yehudah the Nassi (president of the Sanhedrin) made the bold and controversial decision to have the oral tradition written down. ”