स यथोभयपाद्व्रजन्रथो वोभाभ्यां चक्राभ्यां वर्तमानः प्रतितिष्ठत्येवमस्य यज्ञः प्रतितिष्ठति यज्ञं प्रतितिष्ठन्तं यजमानोऽनुप्रतितिष्ठति स इष्ट्वा श्रेयान्भवति ॥ ४.१६.५ ॥
In plain words
And as a man walking on both feet, or a chariot running on both wheels, stands firm, so his sacrifice stands firm; and when the sacrifice stands firm, the sacrificer stands firm after it, and having sacrificed he becomes the better for it.