Being a spiritual person means that you honor your body and care for it as much as you do your psyche. Your body is here for you, to take you through your days on this planet. It's a vital part of who you are. The more you honor the body and keep it healthy, the happier and more relaxed you will be.
Positive thinking is about knowing you have the ability and power to create whatever you want, despite what your own mind or emotions try and make you believe. Repeat: positive thinking is an active choice, a habit. And while it's really hard sometimes to shift there, being able to do so is a critical leadership skill to master.
If I am experiencing the world as a scary place and am caught up in feelings of insecurity, frustration, and hopelessness, that is a direct reflection of some fairly low quality thinking. If I am experiencing a world of possibility coupled with a general sense of well-being, that is a direct reflection of some fairly high quality thinking.