Dear Shamir,
I just wanted to help you clarify what instructor Lion of Judah is trying to tell you about looking into the past and why it is black magic. Why it makes people to disconnect with Christ.
It is all about feeding your ego. The things such as nostalgia or constantly living with your mind in the past makes your decisions and "vision" blurry, because you see through your ego of the past, you identify yourself with the past and with the ego's that pull you into the past. Meaning you can't be here and now. Looking into past is not the same as retrospection. In retrospection exercises you try to be not identified with your mind and ego as much as you can.
If you create your future by identifying yourself with the past (looking back/looking into past) you fall to black magic, because you create the same karma as it was in the past. If you are not looking back, being here and now then you create your future by living in the present moment, here and now. That is white magic. We could say that black magic and white magic are wide statements for this situation. And yes, they are. But overall everything you do can be classified into the black and white magic, because when you work in the esoteric work everything you do is magic. The statement "looking into the past" tells by itself that you are enclosed with the past.
It is really simple. If you are identified with the past. If your mind is constantly in the condition of the past, always wandering in the past, living in the past and etc. makes you like a salt statue (the one that Bible speaks about one, were people would become salt statues if they look back). You just become stagnant in the practices. And then you start to go the wrong way, meaning that you fall to black magic even without noticing it. Because how can you? You can't, your vision is blurred, you are in the past with your mind and emotions, embodied with it.
Retrospection is very different from looking into the past. In retrospection you penetrate into the past by not identifying with it and being here and now.
Just think with your heart, not mind
I hope this will help at least a bit.
Best wishes,
Wingless Eagle.