A Rishi in the Rig Veda is a person who has the revelation of at least one rk mantra of the Rig Veda. The rishi literally hears the mantra by supra-physical methods.
Mantra fully revealed ?
Some persons believe that a rishi sees the complete form of the mantra. It is the so called doctrine of 'apaurusheya ' or non-human origin of the mantras. Rig Veda does not support such a view. The basic intuition or revelation is received from a high plane as mentioned earlier in R.V. (1.164.39). Rishi transcribes this revelations. The appropriate words needed for the mantra becomes formed in the heart as stated in the following mantra.
O Maruts, the hymn of your affirmation (stoma), is fraught with my obeisance (1) , It was framed by the heart, it was established by the mind, O ye Gods (2). ( R.V. 1.171.2 ).
eshah vah stoma maruto namasvan (1),
hrda tashto manasa dhayi devah (2). (R.V. 1.171.2 )
R.V.(1.67.4) also states that the mantra is crafted or formed ( tashtam ) in the heart.
since the rishi has also supra-physical visions of the Truth, he/she is also called a seer (drashtara). There are about 400 rishis in the Rig Veda of whom at least 25 are women. Note that no one is born as a rishi. Being a son or a daughter of a rishi does not automatically give the person the powers of a rishi. A person performs intense spiritual practices including askesis (tapas) to become a rishi. There is no specific procedure for becoming a rishi. One becomes a rishi by grace of the cosmic powers or devatas. In Rig Veda (1.31.16) deva Agni is said to create or form a rishi. Similarly R.Veda ( 9.96.18 ) declares that soma, the Lord of Delight, creates seers. A rishi is identified by two names, his own name and that of his lineage or teacher. The first Sukta of Rig veda Samhita was revealed to Madhuchchhandah Vaishvamitra, a disciple or son of Vishvamitra. The famous Gayatri Mantra ( R.V. 3.62.10) was revealed to Vishvamitra Gathin, i.e., Vishvamitra , son of Gatha.
A rishi can be either celibate or married. A rishi is not only a man of contemplation, but also a man of action. Even though rishis advised the Kings and helped them and their priests in the performance of the rites or the rituals of the outward yajna, the rishis were not priests. In the Vedic period, rishi was considered primarily as the teacher who gave his teaching both orally as well as by occult methods as stated explicitly in the Atharva Veda.
The seven rishis (sapta rshayah ) are mentioned explicitly by name in R.Veda (10.137) namely Bharadvaja, Kashyapa, Gotama, Atri, Vishvamitra, Jamadagni and Vasishta.
Both the collective of rishis and the collective of devatas work harmoniously for the welfare of not only the human beings but for the entire earth. Many legends in the Puranas describing the quarrels among the devatas do not find a place in the Rig Veda Samhita. Note that purana books were composed thousands of years later than the Rig Veda Samhita.
The name of the rishi indicates clearly the sex. The daughter of the rishi Kakshivan is Ghosha Kakshivati, who is herself the seer of R.Veda (10.39-40). There are about 25 women seers of R.Veda, such as Aditi Dakshayani ( RV 10.72 ), Apala Atreyi (RV 8.91), Dakshina Prajapatya (RV 10.107), Yami Vaivasvati (RV 10.10), Vagambirini (RV 10.125) etc.
Rishi (seer) and Sage (vipra): Note that R.Veda makes a distinction between sages and rishis. A sage to whom a rig mantra has been reaveled is a rishi. A sage is a man of wisdom. But all sages are not seers or rishis.
R.Veda (9.96.6) declares the deity Soma as the rishi among sages (rishir vipranam).
R.Veda (9.87.3) declares that the seer (rishi) among the sages (vipra) leads the people (rishiviprah purayeta jananam).