“No one, except possibly the leaders and tzaddikim of this generation, has the explicit, unequivocal knowledge to explain why HKB”H has subjected the world to this virulent organism. What we do know, however, it that it compels us to search our souls and assess our own accountability – ‘cheshbon hanefesh.’
…What specific changes and tikunim should we make in our lives?…
Rabbi Yehoshua ben Levi said: Thunder was created only to straighten out the crookedness within the heart, as it says (Koheles 3, 14): ‘And God has acted so that man should be in awe of Him.’ -Gemara (Berachos 59a)-
…When human beings have sunk into a deep spiritual slumber, usually attributable to their constant pursuit of worldly nonsense, HKB”H needs to wake them up occasionally with a loud, penetrating heavenly voice.
His thunderous voice is intended to make them recognize man’s lack of control over the forces of nature. This will compel them to acknowledge that there is a Master of the Universe. The Almighty created the world and it is controlled by His will.