Comentario sobre Números 10:34

וענן ה׳ עליהם יומם AND THE CLOUD OF THE LORD WAS UPON THEM BY DAY — Seven times is the word ענן used in the account of their journeys alluding to four clouds which screened them on all four sides, one that was above them, one beneath their feet, and one in front of them which leveled the elevations and raised the depressions, and killed all serpents and scorpions (Sifrei Bamidbar 83:1; Mekhilta d'Rabbi Yishmael 13:21:2; Br. d’ Melechet ha-Mishkan 14).

וענן ה' עליהם יומם, it was not traveling ahead of them as it did during the other journeys, seeing that the Ark was performing the task of seeking out a suitable spot for making camp. Instead, it positioned itself above the people.

Seven clouds. The seven clouds are enumerated in Sifri: (1) “The Cloud of Hashem was above them” (here). (2) “Your Cloud stands” (Bamidbar 14:14). (3) “And in a Pillar of Cloud You go” (ibid.). (4) “When the Cloud tarried” (ibid. 9:19). (5) “When the Cloud was raised” (Shemos 40:36). (6) “If the Cloud was not raised” (ibid. v. 37). (7) “For the Cloud of God was over the Mishkon” (ibid. v. 38). All of them were related to the journeying and encampment of Bnei Yisroel. See Nachalas Yaakov and Gur Aryeh.