I'm new to the Hare Krishna movement and Gaudiya Vaishnavism in general (I actually belong to a family of Sri Vaishnavaites), so if this question offends any of you in any way, kindly forgive me.
I'm studying the Mahabharat to great detail these days, and I found out that Krishna asked Arjun to pray to Goddess Durga just before the Kurukshetra War started. Why so? Krishna (being the Supreme God) could've very well asked Arjun to pray to him instead. So, why Durga? I don't intend any disrespect to any goddesses, but Krishna being Arjuna's charioteer and Divinity Himself could've protected Arjuna from any kind of harm, big or small (even if that harm came in the form of the strength of Karna's divine weapons). So, what was the whole significance of Krishna asking Arjuna to pray to Durga? I'm sure Arjuna was completely aware of who Krishna really was. Therefore, what was the purpose behind this entire exercise?
Similarly, Ram also prayed to Goddess Durga just before his final battle with Ravana. Why couldn't he have prayed to Swayam Bhagawan Krishna instead?
Is it that Krishna's sister Yogmaya (Yashoda's daughter) and Goddess Durga are one and the same (in which case, praying to Goddess Durga would be the same as praying to Yogmaya)?
As I mentioned earlier, I'm new to the Hare Krishna movement, so I apologise to all if you find my questions to be stupid and offensive.