Derived from the root ‘argh’ (‘to be valuable’) or ‘arh’ (‘to deserve’), the word ‘argha’ is used in a more technical sense in the dharmaśāstras. It signifies a reception ceremony performed in honour of a bridegroom by his father-in-law, of a newly married couple, on their return to the bride’s house. It is usual to offer madhuparka (a mixture of honey and other ingredients) on such occasions.
The word ‘arghya’ derived from ‘argha’ means a person worthy of ‘argha’ or honour. However, it is used in a more restricted sense to indicate the water perfumed with flowers and mixed with dūrva-grass, rice grains and mustard seeds that is ceremonially offered in ritualistic worship of God, as also to honoured guests. They are expected to receive it and wash their hands with it.
Six persons are enumerated as deserving this arghya: ācārya (teacher), ṛtvij (officiating priest), rājan (king), priya (friend), snātaka (Vedic student who has completed his studies) and vivāhya (bridegroom).
In the sandhyā ritual, arghya is the offering of water to the sun. The worshipper takes water in the joined palms of his hands, repeats the Gāyatrī mantra over it and casts it up respectfully while standing and facing the sun. It is interest-ing to note that the use of dust is allowed for this purpose when water is not readily available.