A Puzzle Long Lost

This key didn't make any sense, I have gone to his old house and to banks asking about it. the last lead I had gotten is that he had buried something when he heard the devil was on his trail. The problem was the location, mainly because there was a church there now. In order to get to whatever is in the box, I needed to desecrate sacred ground. Now I don't usually mind digging up things, no matter where they are. But if the devil is real enough for me to make a deal with him then heaven might punish me for digging up and breaking a church. But I need to start breaking this floor soon, I can't lose control. However, when the pick hit the floor and broke it, a bright light shone on me. Next thing I knew I was hit in the jaw and asked why I was desecrating the grounds. When the light dimmed, I saw an angel standing there. "Listen, i had made a deal...." I started but was quickly cut off. "I know all about you Marshall, your deal, the kills, and your plan. I know your hunting the shadow riders. You know what will happen after that don't you?" He asked "I've read that it could be possible, but without that page, I can't contain the power to carry out my plan," I said trying to sound sincere. Not knowing if this was a friend or foe. "What if I could help you? I'm an archangel, I can teach you to contain your power and I can make teach you more." He said, now seeming more like a friend. I agreed to have him help me, he simply raised a hand and the spirit in me faded. All control I had returned and I felt more at ease with myself. We began to talk more and the angel told me that he had helped the White Rider before. Taught him how to control the power and helped him rebel against the devil. He told me that he could teach me the same and more if I was willing to learn. Before we could start though I had to go through confession, I had told the angel everything I had done, although I'm sure he knew. Everything I told him lifted a weight I thought would never go away. He said I was destined to be the Marshall of Death, but a simple choice could help me redeem everything. I could get my own soul back and still have my abilities. He said before the final fight though there would be two deaths. Two black riders would pass, they wouldn't be able to defeat the devil and carry out my plan, The Marshall of Death and the Black-Marshall would die and be consumed. And this fate couldn't be overwritten.