Good acts done to the virtuous are never fruitless. Such acts never destroy our honour or interest. Since the righteous are characterised by such (noble) conduct they become protectors (of all creatures).
न च प्रसादः सत्पुरुषेषु मोघो न चाप्यर्थो नश्यति नापि मानः। यस्मादेतन्नियतं सत्सु नित्यं तस्मात् सन्तो रक्षितारो भवन्ति॥