Комментарий к Бамидбар 2:3

קדמה means IN FRONT, which is expressed by קדם; and which side is it? The east side (מזרחה), and accordingly the west is termed אחור, the back side of the world (cf. Rashi on Exodus 27:13 and Note thereon).

והחנים קדמה מזרחה, "And the ones encamped in the east toward the sunrising, etc." The reason this verse commences with the conjunctive letter ו is that it follows the command to establish the camp around the Tabernacle and only proceeds to give additional details.

This is the eastern side. One might ask: From where does Rashi know this? One may explain that since west is called the rear one may infer that the front is the east. An alternative explanation: A hei at the end of a word is in place of a lamed at the beginning. Thus, since קדם means פנים (front — lit. face) it is clear that קדמה would mean לפנים (towards the front) while the word מזרחה would also mean towards the east. (Gur Aryeh) One might ask: Why does the Torah write the repetitive phrase קדמה מזרחה (in the forefront to the eastern side)? It appears that it wishes to teach us that because Yehudah held the kingship he was to be given the side that was most important. Therefore the east was referred to in terms of being “first” and “in the forefront.” If the Torah had written מזרחה or קדמה alone we would not have learned this point.