The great sign is shmitta. Reb Zadok of Lublin points out that the faith represented by desisting from work one day a week is greatly overshadowed by the demonstration of faith by refraining from farming for one year in seven. That kind of behavior requires a total reliance on Hashem and His grace. Shmitta is the ultimate exhibition of our faith and belief. All these views are predicated upon a mystical bond being forged by our demonstration of belief.
Divine bounty blesses our earthly attempts at spirituality.
We don't need this world we need Hashem. For this we turn to the Maharal of Prague. Reb Loewy of Prague in Tiferet Yisroel chapter forty describes the significance of the number seven. He points out that physical reality as we know it is defined by the number six. There are three directions or dimensions which go in both ways.