daf bit: Menachot 99

The rabbis link torah and life -- that is, torah is the source of sustenance -- in many places. Today's g'mara teaches: R. Yochanan and R. Eleazar both said: the torah was given in forty days and the soul is formed in forty days. Therefore, whoever keeps the torah his soul is kept, and whoever does not keep the torah his soul is not kept. Reish Lakish said: he who forgets one word of torah (willfully, not accidentally, it appears) transgresses a negative precept, as it is written: only take heed to thyself and keep they soul diligently, lest thou forget things (Deut. 4:9). (99b)