YV 5.7g

They offer a beast to Prajapati-Prajapati is the sacrifice that the sacrifice may not be abandoned. For six months (as they go) hence the Brahman's Saman should be the 'victorious'. The 'victorious' is the holy power (Brahman); verily they go winning the world of heaven by the holy power (Brahman); for the world of heaven is as it were opposite from hence. When they come thence the Brahman's Saman for six months should be 'O Indra, bear us strength, as a father to his sons. Guide us, O thou that art much invoked, on our path. Living, may we attain the light.' The light is this world, the light is offspring; verily they come, gazing on this world by repeating When the gods had come to the end, their power and strength departed. They won them again by the Kroça (Saman), and that is why the Kroça has the name. In that they sing the Kroça at the end of the pit, they win power and strength at the end of the sacrifice. They sing the Sattra syarddhi (Saman) at the end of the Ahavaniya; verily, making Agni a witness, they advance to prosperity. They sing the Prajapater Hrdaya within the shed; verily they win his favour. They sing the Çloka (Saman) in front of the Sadas [1], the Anuçloka (Saman) behind; verily fame is their portion at the end of the sacrifice. The Adhvaryu sings nine (verses). Nine are the breaths in man; verily he places breaths in the sacrificers. All of them are addressed to Indra; verily he places power (indriya) in the breaths. He sings without the Pratihara. Therefore a man can contract all the other members (of the body) except the head, but the bead not. The Rathantara (Saman) has the Pañcadaça (Stoma); verily they win power. The Brhat has the Saptadaça [2], for the winning of food; verily also they are propagated by it. The Bhadra (Saman) has the Ekavinça (Stoma) with Dvipada verses, for support. The wives (of the sacrificers) sing, for offspring, for propagation. Prajapati created offspring; he desired, 'May I gain the kingship over them.