It is customary to sound the shofar during the month of Elul, the month leading up to Rosh Hashanah.
Maimonides says that the Shofar can be seen as a "wake up call" - as if it is calling out and saying:
“Sleepers, be roused, from your sleep! Slumberers, wake from your slumber! Search your deeds and return in teshuvah...” (Maimonides, Laws of Teshuva 3:4)
The path to teshuva, repentance, is a two-step process. The first step is to arouse and wake from our sleep or slumber, and the second, to search our deeds.
While we are sleeping we normally have no conscious desire to disturb our sweet sleep and awaken. The same is true when we might be in a spiritual slumber - we may become complacent with life and uninterested in disturbing our peaceful obliviousness. Therefore, says Maimonides, the first step toward teshuvah must be to wake from our slumber so that we can become aware and make an assessment of our spiritual condition. Only then will we be in position to begin to earnestly work towards return.
- Adapted from Lightpoints