Rashi: He meant that he had two spirits - one in his mouth and one in his heart. With his mouth he professed to be in league with the other spies, but in his heart ¹ he was prepared to speak the truth. Hence he was able to silence them earlier in the Parshah. ²

Rashi: It means 'his heart ¹ was completely with Me'.

Targum Onkelos and Targum Yonasan: It means that he was complete in his Yir'as Shamayim.

Rashi: It refers to Chevron, which Calev alone visited. ¹

Rashi: It means that his descendents ¹ will dispossess the giants and the people who live there), whereas Yirashenu' would mean 'he will possess it'.

Seforno: It means that Calev will pass it on to his children. ²

Ramban: Because the main point here is the fact concerning Calev's inheritance in Eretz Yisrael, whereas Yehoshua's reward - that he became Moshe's successor - does not belong here. ¹ Moshav Zekenim ? Hashem placed Calev before Yehoshua, since he was the first to argue with the Meraglim ? "va'Yahas Calev;" Moshe, on the other hand, placed Yehoshua first, due to his Chochmah.

Riva and Moshav Zekenim: Because the Torah is discussing Calev's inheritance, and Yehoshua did not have sons to inherit him.

Rosh: Because, when the other Meraglim said 'We trust Calev,' ² he climbed on to a bench, and all Yisrael, who were screaming at Moshe, were silent, and he procceded "Im Chafetz banu Hashem ?",

Oznayim la'Torah: Because, when Calev initially responded to the spies allegatons, Yehoshua was silent. ³ And it is only later in Pasuk 30, after the rebellion broke out and he joined Calev in renting his garments and announcing "Tovah ha'Aretz ... ", that he is mentioned, together with Calev. However even there, in spite of his superior standing, he is mentioned after Calev, because of his initial laxness.