וַיֹּֽאמְרוּ֙ כָּל־הָ֣עֵדָ֔ה לִרְגּ֥וֹם אֹתָ֖ם בָּאֲבָנִ֑ים וּכְב֣וֹד יְהוָ֗ה נִרְאָה֙ בְּאֹ֣הֶל מוֹעֵ֔ד אֶֽל־כָּל־בְּנֵ֖י יִשְׂרָאֵֽל׃ (פ)
Ma tutta la congregazione ordinò di lapidarli con pietre, quando la gloria dell'Eterno apparve nella tenda dell'incontro con tutti i figli d'Israele.
Rashi on Numbers
לרגום אתם [BUT ALL THE CONGREGATION BADE] TO OVERWHELM THEM WITH STONES — them viz., Joshua and Caleb.
Or HaChaim on Numbers
ויאמרו כל העדה לרגם אותם באבנים, The whole congregation said to stone them. Why did the people not react in a similar fashion as soon as Caleb said in 13,30: "we can certainly go up and inherit this land?" Presumably the people did not pay any heed to the testimony of a single individual, as such testimony is halachically meaningless when the witness is confronted by two or more witnesses disputing what he said (compare Deut. 19,15). Now that Joshua had joined Caleb, the two represented a valid set of witnesses and the fact that they were outnumbered was halachically irrelevant (compare Makkot 5). In law, the two sets of testimony ranked equally. As a consequence, the two testimonies cancel each other out so that legally speaking the people did not have whom to rely on. Feeling frustrated, the people wanted to kill the witnesses who made up the minority report.
Siftei Chakhamim
Yehoshua and Caleiv. Not Moshe and Aharon, because they did not say anything.