Why didn't lord krishna gave mantra of sudarshan chakra, vaishnavastra, narayanastra and kamodgi gada to abhimanyu if he was guru of him
Answers
because those astra is dedicated to god itself not all as a result did u ever got a doubt that why we are not having those powers like gods have and the powers to do tapasya. Because In those days they are most powerful and having those powers to do so . but these days these days are ordinary days no power no bhakti to god as a result those astra's belongs to lord Vishnu and his avatar not to all . then how did parashuram have that astra and he gave to lord krishna because parashuram is also an avatar of lor vishnu so he is having other no one can hold that sudarshan chakra or any astra .only god can so krishna didn't gave the mantras of the astra because abhimanyu couldn't hold it . For more information see vishnupuran in dd national
if you are in pain say this mantra I tried it many times and it really worked.