I am seeking something different from all that has already been touched upon.
I am aware of the fact that Vedas are 'Apaurusheya' and 'Anaadi' and that they were revealed to the sages by the Gods during meditation. And after revelation the sages gave them to the disciples and people by putting them into the form of Sanskrit verses as hymns. And Vedavyasa is the one who gave Vedas the textual form. So no queries on that. And so please, no discussion on that.
What I wanted to know is; if there is any historical or scriptural or customary evidence or information regarding, '"What was the qualification for a sage/person whose hymn would be accepted as a Vedic hymn?"
Let me elaborate below;
Not all the Vedic hymns were composed instantly by one sage, in one revelation. There are numerous sages who composed the hymns at diferrent times. The Vedas were composed for thousands of years. As and when a new hymn was revealed and composed it was incorporated into the corpus of the already prevalent body of hymns of Vedas. So for a hymn to be accepted as a Vedic verse, it certainly had to have some qualities, moreover the composer too had to have some qualities.
There must have been some qualification as to which sage's which hymn becomes part of the vedic scripture. Certainly not all hymns composed by any person, who said this verse was revealed to me by the Gods, could become a vedic hymn.
In that case "What is the qualification for a hymn to be accepted as a vedic hymn and what is the qualification of a sage to compose a vedic hymn?"
So the question is; "Who were qualitatively regarded as the ones who could compose Vedas?"
Further, it is also said that, even today, Vedas are edited by certain people who have the sole authority to do so. Is this true? If so who are they? Where do they derive this authority from?