Bhagavad Gita 3.21

यद्यदाचरति श्रेष्ठस्तत्तदेवेतरो जन: |
स यत्प्रमाणं कुरुते लोकस्तदनुवर्तते

Translation

Whatever actions great persons perform, common people follow. Whatever standards they set, all the world pursues.