Why are the Meraglim called Na'arim (youths? Midrash Tanchuma says that one of them was Kalev. He was 78 years old!), and in verse 25, they are called angels?
Rashi: They needed to go zealously (quickly), and they became like youths. The first night they were like angels, who guarded themselves from sinning with Rachav the harlot.
Radak: Any servant is called a Na'ar, even if he is old, like "[u'Meshareso] Yehoshua bin Nun Na'ar" (Shemos 33:11; he was 56 at the time). These spies were servants of Yehoshua or one of the esteemed Yisraelim.
Here it says that Rachav and her family were outside the camp. Verse 25 says that they dwelled "b'Kerev Yisrael"!
Radak: They were outside the camp until they converted. After they converted, they dwelled among Yisrael.