Shatapatha Brahmana 11.5.5.1

11.5.5.1

devānvā ūrdhvāntsvargaṃ lokaṃ yataḥ asurāstamasāntaradadhuste hocurna vā asyānyena sattrādapaghāto'sti hanta sattramāsāmahā iti

Now, when the gods were passing upwards to the world of heaven, the Asuras enveloped them in darkness. They spake, 'Verily, by nothing else save a sacrificial session is there any way of dispelling this (darkness): well, then, let us perform a sacrificial session!'