About Nes, Hishtadlut, and Teva

The Gemara in Yoma 38A tells us the story of Beit Garmu, the family that were the only ones who knew how to bake the Lechem Hapanim to perfection. This family, mentioned in the Mishna, was intent on protecting their turf and therefore would not teach anyone else the skills necessary to bake the Lechem Hapanim so that it didn't crumble and would stay fresh. The Chachamim, we are told, imported experts from Egypt to try their hand to break the Beit Garmu monopoly. They were able to get the consistency right but could not master the technique to the extent needed to keep the bread fresh for the duration of the week that it was out on the Shulchan. Tosfos Yeshanim asks why do they need to go to this great length to keep it fresh if we know that one of the nisim in the bais hamikdash was that the lechem hapanim stayed fresh by way of a miracle. Tosfos Yeshanim answer that the miracle only started after everything that can possibly be done by man was done.

I believe that this is a very basic lesson in general in God's intervention and hashgacha in this world. Even in things that we can expect hashgacha they will only start after man has exhausted all that he can do. Miracles and, I suggest hashgacha, will not replace what man can do. Hishtadlut is not a condition precedent for godly intervention it is a way of getting to the point where God takes over