I have always seen spirits. I believe that they are either angels or demons who either protect and comfort or intimidate and sow doubt.
When I was a boy, every time I closed my eyes for more than a blink, hundreds of white spirits would come flying at me. I would twitch and flinch when I closed my eyes, but they would get very close then go around. I also used to see dark spirits lurking at windows outside my house. Once I locked myself in a closet with a cordless phone because I thought that someone was out there.
I firmly believe that the dark spirits were stuck outside because of the spirituality of my parents. When I moved into my own house, they decided to test me. One night right when I laid down for bed, I heard dings of my laptop starting up. As soon as the noise finished I heard the lid closing again and the little latches locking in place. I grabbed my shotgun and searched the entire house to no avail. A couple of days later, I started at one end of my house and was praying the blood of Jesus over the rooms, the windows, and the doors to protect it from the dark spirits. When I got to the living room where the laptop incident took place, I was praying and it got freezing cold in the room and I could feel the struggle taking place. I finally have peace in my home.
Another time, I was walking in the hospital SICU where I was working at the time in the middle of the night and I saw the angel of death. As soon as I realized what it was, it snapped out of view. I never heard if anyone passed that night.