Verse 2.4.2

न हाप्सु प्रैत्यप्सुमान्भवति य एतदेवं विद्वान्सर्वास्वप्सु पञ्चविधंसामोपास्ते ॥ २.४.२ ॥
॥ इति चतुर्थः खण्डः ॥

na hāpsu praityapsumānbhavati ya etadevaṃ vidvānsarvāsvapsu pañcavidhaṃsāmopāste || 2.4.2 ||
|| iti caturthaḥ khaṇḍaḥ ||

2. He who performs the fivefold Sāma worship in all forms of water, knowing it thus, will never be drowned in water unless he wishes to be, and he will have as much water as he wants.

Word-for-word explanation:

Yaḥ, he who; evam, as mentioned; etat, this [Sāma]; vidvān, having known; sarvāsu apsu, in all forms of water; pañcavidham sāma upāste, performs the fivefold worship of Sāma; [saḥ, that worshipper]; apsu, in water; na ha praiti, does not die [unless he wants to]; apsumān bhavati, he has much water at his disposal. Iti caturthaḥ khaṇḥaḥ, here ends the fourth section.

Commentary:

A person who performs this Sāma worship, taking water as the object of worship, will never be drowned unless he himself seeks his death that way. Also, he may be so lucky about water that he will even get it in a desert.