Here is a humorous quote from John MacArthur about human limitations from his sermon on Mark 10:23-31.
God can do all things that He determines to do. (Daniel 4:35)
That, however, is not true of us. Although there are people today who would like to make us think we can do anything, it is a deception. So common for people to say, “You can do anything you want. You can accomplish anything you desire, just believe in yourself.”
That is so ridiculous, of course. It’s the comment of a deceiver, or deluded person, and I just began to think about that a little this week and I found some things that you can’t do.
You…well, there are a lot, I’m going to give you just a few. You can’t tickle yourself, you can’t lick your elbow. Okay? We’ll start there. And if that’s not profound enough for you, you can’t sneeze with your eyes open and you can’t slam a revolving door. And you cannot, according to one source, move your leg in a clockwise position in a circle and simultaneously draw a six. Don’t try that, you may fall over.
Or, as Winston Churchill said, “There are three impossible things for me to do.” Churchill said, “One, climb a wall leaning toward me. Two, kiss a girl leaning away from me. Three, speak to a group on a subject about which they know more than I do.” He was a modest fellow, to put it mildly.
Well, those are trivial things to think about but for anybody to assume that we can do anything we want to do is pretty ridiculous. There are all kinds of limitations on what we are able to do. There are limitations of talent. There are limitations of opportunity. There are limitations of circumstances. There are limitations of time. We all understand that. Life is full of limitations. Some of them belong to us and some of them basically are part of the environment in which we exist. You can’t do anything that you want to do, necessarily, just because you want to do it. And believing that you can do it doesn’t alter the fact that you can’t do it if you can’t do it. That kind of folly belongs in the self-esteem psychology which is deluding people with exaggerated opinions of themselves.