Rig Veda
सा॒कं हि शुचि॑ना॒ शुचि॑: प्रशा॒स्ता क्रतु॒नाज॑नि । वि॒द्वाँ अ॑स्य व्र॒ता ध्रु॒वा व॒या इ॒वानु॑ रोहते ॥ साकं हि शुचिना शुचिः प्रशास्ता क्रतुनाजनि । विद्वाँ अस्य व्रता ध्रुवा वया इवानु रोहते ॥
The pure regulator (of the sacrifice) is born verily together with the holy act; the wise (worshipper) performs all his, (Agni's), prescribed rites in succession, as the branches spring (from a common stem).
english translation