It seems from Rashi that there was a period of time that overlaped between the 7 clouds and the pillar of fire , whereby, both ruled simultaneously........................

A question can be asked, what lesson can be learned from this occurance? Why did the 7 clouds and pillar of fire have to overlap?

The Torah is teaching us a tremendous lesson in the art of proper conduct and common courtesy................We see that the 7 clouds always waited before departing to greet and acknowledge the pillar of fire, and visa versa...................

Perhapes we should take a lesson and always acknowledge and honor our fellow friend with appreciation and kindness...

Similarly, in Pirkei Avots 2:10 it states the following: Rabbi Eliezer said, " Your friends honor should be as precious to you as your own..........................................." Deep down we all want to be appreciated and acknowledged............Perhapes, if we start to honor others properly, we will receive the same in return and make the world a better place to live in. All we actually need to do is simply smile at another person.....There is no better greeting than a smile......This might seem very small and trivial, but the cummulative effects can be trully great and significant...............Have a good Shabbos