Shatapatha Brahmana 10.1.5.4

10.1.5.4

athāto yajñavīryāṇāmeva sāyamprātarha vā amuṣmiṃloke'gnihotrahudaśnāti tāvatī ha tasminyajña ūrgardhamāse'rdhamāse darśapūrṇamāsayājī caturṣu-caturṣu māseṣu cāturmāsyayājī ṣaṭsu-ṣaṭsu paśubandhayājī saṃvatsare-saṃvatsare somayājī śate-śate saṃvatsareśvagnicitkāmamaśnāti kāmaṃ na taddhaitadyāvacataṃ saṃvatsarāstāvadamṛtamanantamaparyantaṃ sa so haitadevaṃ vedaivaṃ haivāsyaitadamṛtamanantamaparyantam bhavati tasya yadapīṣīkayevopahanyāttadevāsyāmṛtamanantamaparyantam bhavati

Now, then, as to the powers (conferred by the performance) of sacrifices. Verily, he who (regularly) performs the Agnihotra eats food in the evening and in the morning (when he comes to be) in yonder world, for so much sustenance is there in that sacrifice. And he who performs the New and Full-moon sacrifice (eats food) every half-month; and he who performs the Seasonal sacrifice (does so) every four months; and be who performs the animal sacrifice (twice a year, eats food) every six months; and the Soma-sacrificer once a year; and the builder of the fire-altar at his pleasure eats food every hundred years, or abstains therefrom; for a hundred years is as much as immortality, unending and everlasting: and, verily, for him who knows this, there shall thus be immortality, unending and everlasting; and whatever he as much as touches, as it were, with a reed, shall be for him immortal, unending and everlasting.