अन्नाभावे मृत्युः शालिभिरन्नानि शालयो वृष्ट्या।
वृष्टिस्तपसेति वदन्न् अमृत्यवे तत्तपश्चरतु॥
Without food comes death; rice gives food, rain gives rice; rain comes through penance. Therefore, one should do penance for immortality.