One of the very best things that you can do for yourself and your health, both mental and physical is to believe.
Believing is to feel sure of something. When you can wake up each morning and choose to believe, you can accomplish nearly anything.
I think that Believing is necessary in two ways. First, the ability to believe in yourself. You have to really know that you can do it. Believe that you will make it to that yoga mat everyday, believe that you can get the promotion at work, believe that you are capable of being a good mother, wife and individual. What we tell ourselves is what we believe.
Second, believing that things will work out. This one is far more difficult for me. Though, when I can choose to believe that everything will be OK and all will work out, I am far less stressed. We are talking sleep better, enjoy life more and find myself with a smile more often than not.
I wholeheartedly think that what we believe we can achieve. I have seen this so many times in my own life and that was only when I was looking! What is the point walking around thinking that you are doomed and nothing will every work out? Might as well believe in yourself and in your life, because when you start living like that others will have no choice but to believe in you too.