The Yoga of the Vision of the Cosmic Form the eleventh discourse of the Bhagavad Gita, we find that all doubts have been removed from Arjuna's mind and he is now ready for cosmic vision. Krishna grants him the ability to see the Lord as the cosmic manifestation that is the reality of existence. He sees that nothing is manifest without the will of the Lord and that the Lord is responsible for all.1-vqwyt-yoassajd76xgub4w 

Now behold, O Arjuna, in this, My body, the whole universe centred in the one—including the moving and the unmoving—and whatever else thou desirest to see!

that happens, good and bad.

It is further explained that one cannot see the Lord in this way through regular human vision. It is through intuition, a divine experience that one is able to see.

I see Thee without beginning, middle or end, infinite in power, of endless arms, the sun and the moon being Thy eyes, the burning fire Thy mouth, heating the entire universe with Thy radiance.

Arjuna sees within the image of the lord, all those people that he was so concerned about killing rushing to their deaths. It was the will of the lord and so happened.
Arjuna becomes fearful because of this sudden expansion of consciousness and asks that the Lord go back to the form of Krishna.The Lord tells him to look once again, without fear upon his form. It is then that Arjuna is able to see the compassionate, gentle Lord and he loses his fear. Once again, Arjuna is told that he who comes to the Lord with a devotional heart and who practices the teaching of the Gita, showing no wrong-doing to other creatures, becomes one with the Lord.
While I at times find the Gita confusing because Arjuna is being told to fight in a war and to be ok with killing, I think that the message is more about nothing happening without the will of the Lord. Everything that transpires does so because of a universal energy if you will. If we consider that we are all part of this universal energy as opposed to the Lord being a separate being (which is what I believe), then everything that we do affects all of us. We do our duty, whatever that may be, without necessarily knowing what ripple that action causes in another part of the world or in another person's life. We can never really know what's good or bad in our lives because we aren't able to see the overall picture, which is what Arjuna was shown. When you add time into that equation it becomes even more complicated!
I would love to know your thoughts in this, or any part of the Gita. I'd love to hear from you!