Rashi's explanatory note is this: "Shake off the salt from the
flesh and it becomes fit only for dogs. The soul is the salt
which preserves the body; when it departs, the body putrefies."
Four things require fortitude in the observance:--The law, good works,
prayer, and social duties. Respecting the law and good works it is
written (Josh. i. 7), "Be thou strong and firm, that thou mayest observe
to do all the law;" in which the word "strong" refers to the law, and
the word "firm" to good works. Of prayer it is written, "Wait on the
Lord; be strong, and He shall make thine heart firm; wait, I say, upon
the Lord" (Ps. xxvii. 14). In respect to social duties it is written (2
Sam. x. 2), "Be strong, and let us strengthen ourselves for our people,
and for the cities of our God."
THE TALMUD, _Berachoth_, fol. 32, col. 2.