Chandogya Upanishad 3.1.2

The first rays of the sun seen in the east are like the honey cells of a beehive. In these cells are the bees, which are compared to the Ṛk mantras. The sun in the morning is red, like honey. The Ṛk mantras are called bees because bees produce honey, and the Ṛg Veda is called the flower because that is where the bees get the nectar to make the honey.

Here, the term Ṛg Veda does not mean words. It means work—that is, the rituals prescribed in the Veda. It is the result of the rituals that is described as honey. Just as the bees collect the juice from the flowers and change it into honey, so the Ṛks seem to collect from the sacrificial fire the liquid, consisting of the soma juice, butter, etc., from the oblations. This is called nectar because after the ingredients have been in the fire, they are transformed into the sweetest and purest thing possible. The result of the sacrificial ritual is the nectar (amṛta), because it leads to immortality. The word amṛta means both ‘nectar’ and ‘immortality.’