DEUT99 A person must place himself on a temporary footing in this world and a permanent one in relation to his service [of the Eternal]. With worldly matters, he must be content and satisfied with whatever he happens to find; he must take from what comes his way, shun ease and be prepared to work and toil; and his heart should be secure in its trust in the Eternal, without fear of the consequences that time and its afflictions may bring. But you may object: "We find that the Sages required one to protect himself carefully, wherever he is, and not place himself in danger, even if he is a tzaddik and a man of deeds. And, they said (Kesubos 30a): 'Everything is in the hands of Heaven except [illnesses that result from] the cold and the heat,' and it is clearly written [this verse]: 'You shall be very careful of yourselves.' So we see that one cannot decide to 'have trust in the Eternal' in all circumstances, as it further states: 'Even for a mitzvah [one must be careful not to endanger himself] [see Pesachim 8b]." One has to distinguish between different kinds of fear: there is fear that is appropriate and fear that is irrational. There is "trusting in the Eternal" and there is recklessness. For the Master, Blessed be He, created man with an intelligent mind and the ability to reason, so that he would be able to conduct himself properly and safeguard himself from the noxious phenomena that have been created to punish evildoers. One who chooses to ignore wisdom and is willing to place himself in danger is not displaying trust but rather recklessness. [Such a person] is sinning by flouting the will of the Creator, may His Name be blessed, who wants man to protect himself.