Being 'simple' implies a straightforward faith in our creator, no calculations or wondering or complications, a simple faith, a direct connection. 'Simple' is a very high level nowadays.
A Simple Jew, a great blog, today presents a simple story that I highly highly recommend reading: Zusia is very hungry and desires to eat something!
It was the custom of Rebbe Zusia of Anapol, to recite his morning prayers at length. After he concluded, he would retire to his room next to the shul. Once there, he would open the window and, lifting his eyes to the heavens, call out, "Ribbono shel Olam (Master of the Universe), Zusia is very hungry and desires to eat something!"
Every morning, his attendant would wait until he heard Reb Zusia's appeal, then he would bring in Reb Zusia's morning meal of cake with a little schnapps. One morning the attendant thought to himself, "Why doesn't Reb Zusia ask me directly for his meal. In fact, who does he think he is fooling by calling out to G-d like that? He knows full well that I bring him his food everyday." So on the spot he decided that the next morning he would not bring Reb Zusia's meal when he called out. He would just wait to see what would happen and where Reb Zusia's would look for his meal.
Read the whole thing!