“Vnishmartem M’eod L’Nafshoseichem – Guard your souls, very much (Deut. 4:15).’
The Talmud (Brachos 32b) cites this as the source for watching your health.
Now, this seems odd…it seems to have nothing at all to do with physical health — only spiritual health!
Let’s translate the verse above more carefully, and literally: ‘Vnishmartem M’eod L’Nafshoseichem – And you should guard, very much, for your souls.’
The guarding was something for your soul, not of the soul. From here the Sages derive that Moses’ instructions were to do a service for the soul.
The Torah did not need to tell us to watch our health merely to survive. The lesson is to channel and enhance that drive for a higher purpose so you can have the strength, intellect, and extra days and years to pursue spiritual goals in full capacity.”