Before the Meraglim left on their mission to Eretz Yisroel, Moshe changed Yehoshua’s name and davened for him to be saved from the Meraglim. Kalev on the other hand did not receive any special Bracha. He made his way to Chevron to be Mispalel on his own behalf. Why didn’t Moshe daven for Kalev as well?
Rav Elyashiv answers that Yehoshua was Moshe’s talmid and there was no doubt that he would stay in his tzidkus no matter the circumstances. All the Meraglim knew this. Moshe was afraid that if things turned sour like they in fact did, Yehoshua’s life would be in jeopardy because the Meraglim may want to kill him since Yehoshua would outwardly take a stand against his peers. For this Moshe davened that Yehoshua would remain safe and unharmed.
Kalev on the other hand took a covert approach. He would appear to agree with the Meraglim until he arrived safely back to the Midbar. Because of this he was not concerned with his physical safety. He was more concerned that by outwardly going along with the Meraglim it may influence his “Pnimiyus”, his inner soul and he would end up just like them.
For this says Rav Elyashiv, a tzadik’s tefilos are not sufficient. Since this is purely a matter of “Bechira”; individual choice, a person must daven on his own behalf. Therefore Kalev went to Chevron to daven for himself.
