why Krishna spoke Bhagavad Gita to Arjuna

Question: Why does Krishna tell Arjuna to be detached from the results when Krishna wants the result of establishing dharma and wants Arjuna to be [...]

As the Bhagavad Gita is a dharma-saṁvāda and Yudhishthira is known as Dharmaraja, why did Krishna speak the Gita to Arjuna rather than to Yudhishthira? [...]