Shlach Lecha, 

Rashi : שלח לך אנשים. לָמָּה נִסְמְכָה פָרָשַׁת מְרַגְּלִים לְפָרָשַׁת מִרְיָם? לְפִי שֶׁלָּקְתָה עַל עִסְקֵי דִבָּה, שֶׁדִּבְּרָה בְאָחִיהָ, וּרְשָׁעִים הַלָּלוּ רָאוּ וְלֹא לָקְחוּ מוּסָר (תנחומא):

שלח לך אנשים SEND THOU MEN — Why is the section dealing with the spies put in juxtaposition with the section dealing with Miriam’s punishment? To show the grievousness of the spies’ sin: because she (Miriam) was punished on account of the slander which she uttered against her brother, and these sinners witnessed it and yet they did not take a lesson from her (Midrash Tanchuma, Sh'lach 5).

Of these 12 princes, one was Moshe's greatest student, Hoshea. Anticipating the possibility of trouble, Moshe added the letter 'yud' to Hoshea's name giving the now, Yehoshua, an 'injection' of holiness to help protect him from that trouble. 

Ohr HaChaim: We already mentioned that our sages said that Moses prayed concerning Joshua. Why did he have to change his name in addition? Perhaps Moses wanted to give Joshua additional power to resist wicked advice seeing that the first three letters of his name now represented the three letters making up the tetragram. The letter י which Moses added to Hoshea's name has a numerical value of 10 and symbolised that he could resist the advice of ten of his colleagues. It would also eventually enable him to inherit the share of ארץ ישראל that the ten wicked spies would forfeit due to their conduct. This is based on a comment in Chagigah 15 

R’ Bachya: Our sages in Sotah 34 comment that Moses added the latter י to Hoshea’s name so that the letters י-ה at the beginning of his name represented a prayer that he should be saved from making common cause with the majority of the spies. 

Daat Zakenim . When Sarah’s name שרי had been changed to שרה, she had lost a letter, i.e. the letter י. Joshua now received this letter. 

Discuss humility. Last week 

Sarah 

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