After hearing of G-d’s plan to keep them in the desert for 40 years, some of the Jewish people reconsidered their agreement with the spies’ assertion that the Land of Israel could not be conquered. They organized their own army and attempted to enter the land on their own. But because they went against G-d’s will and lacked Moses’ leadership, the nations who lived near the border of the land repulsed them
Numbers 14:40
The people had initially refused to proceed toward the Land of Israel because they believed that it was impossible to conquer it, even with G-d’s help. What caused them to suddenly abandon their skepticism? After all, Moses did not show them any new miracles, nor did G-d appear and perform some heavenly exhibition of His strength.
Our sages point out that every Jew inherently believes in G-d. Thus, even while the people were voicing their skepticism, they still believed in Him; their belief was just overshadowed temporarily by their emotions. Therefore, as soon as G-d rebuked them and informed them of the severity of the consequences of their lapse of faith, their inherent faith was awakened.
The same is true of many of the doubts from which we occasionally suffer. Our questions are often due to an exaggerated material perspective on life. Deep within our hearts we indeed believe in G-d. In such cases, the way to overcome our doubts is not to attempt to answer them directly but simply to reawaken the pure faith that lies dormant within us.
—from Daily Wisdom