CHĀNDOGYA UPANISHAD · 2.5.2

कल्पन्ते हास्मा ऋतव ऋतुमान् भवति य एतद् एवं विद्वान् ऋतुषु पञ्चविधं सामोपास्ते ॥

kalpante hāsmā ṛtava ṛtumān bhavati ya etad evaṃ vidvān ṛtuṣu pañcavidhaṃ sāmopāste ॥

The seasons belong to him, nay, he is always in season (successful) who knowing this meditates on the fivefold Sâman as the seasons.

F. Max Müller · The Upanishads, Sacred Books of the East 1 (1879)