I would like to ,Bezrat Hashem, propose an original answer as follows: A tent represents privacy, in essence Mans inner self..........................When the Israelites murmured,they were really complaining internally to themselves. They did not fully trust in Hashem..........They had doubts......However, these doubts were deep rooted inside of themslves. This was their downfall, in that they never really examined how they actually felt about The Torah and G-d.There was something definately lacking in their internal trust and faith in Hashem. The Israelites had neglected to properly examine and correct their internal beliefs.Yet, we must learn from their mistake and examine how we actually feel about our present attitudes towards the Torah and Hashem.

It states in Barochot 17a the following: " A man should always be "naked" in the fear of Heaven"................... This means that in order for a person to trully come to a deeper appreciation of fearing G-d, he must shed all internal doubts regarding his true feelings about the Torah and his relationship to G-d. In essence , one must be "naked" before G-d emptied of all internal doubts.If we are to reach higher plateus in our "service to G-d" ,perhapes a reexamination of our internal belief systems is a good start. Have a good Shabbos................................................