Why should we bother about researching when the evidence is there from the authority?
So to save time, to save trouble one has to accept the authority, actual authority. This is the Vedic process. And therefore Veda says, tad vijñānārthaṁ sa gurum evābhigacchet (MU 1.2.12). Tad vijñānārtham, in order to learn that transcendental science, one has to accept guru. Gurum eva, certainly, one must. Otherwise there is no possibility. Therefore Kṛṣṇa is accepted here as the spiritual master of Arjuna, and as the spiritual master or father or teacher has got right to chastise his son or disciple... A son is never dissatisfied when father chastises. That is the etiquette everywhere.