Shatapatha Brahmana 14.1.2.18

14.1.2.18

prajāpatirvā eṣa yajño bhavati ubhayam vā etatprajāpatirniruktaścāniruktaśca parimitaścāparimitaśca tadyadyajuṣā karoti yadevāsya niruktam parimitaṃ rūpaṃ tadasya tena saṃskarotyatha yattūṣṇīṃ yadevāsyāniruktamaparimitaṃ rūpaṃ tadasya tena saṃskaroti sa ha vā etaṃ sarvaṃ kṛtsnam prajāpatiṃ saṃskaroti ya evam vidvānetadevaṃ karotyathopaśayāyai piṇḍam pariśinaṣṭi prāyaścittibhyaḥ

Verily this sacrifice is Pragâpati, and Pragâpati is both of this, defined and undefined, limited and unlimited. Whatever one does with a Yagus formula, by that one makes up that form of him (Pragâpati) which is defined and limited; and whatever one does silently, by that one makes up that form of him which is undefined and unlimited: verily, then, whosoever, knowing this, does it on this wise, makes up that whole and complete Pragâpati. But he also leaves over a lump of spare (clay) for expiations.