Navratri is traditionally celebrated at the beginning of autumn every year, when everything in nature starts undergoing transformation. This is the time that the season changes from a more extreme season to a more moderate season of autumn.
When nature is in balance, it helps for us to also get into that balance. That's why, for any spiritual practice, sandhya or the interval is supposed to be the most ideal time. So, even if you're doing your meditation morning, afternoon, evening when the transition is happening in nature, when there is balance in nature, when it's neither this nor that, that's the time it is good to meditate. So, the Navratris are a great time to meditate.
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