Mantra 1

स य इदमविद्वाग्निहोत्रं जुहोति यथाङ्गारानपोह्य भस्मनि जुहुयात्तादृक्तत्स्यात् ॥ ५.२४.१ ॥

In plain words

He who makes the fire offering without knowing this is like one who takes away the coals and offers into the ashes.