I agree with Patrick. Say I were to choose the priesthood when God created me to get married, or the other way around. Both are holy and beautiful choices, so maybe I am not doing exactly what God created me to do. Yhat doesn't mean I wont receive blessings and graces from God
and that's just it. We made a choice based on our free will. Since we don't really know what Gods will is for us, we make a choice. Now, determining between good and evil, then yes, if we choose knowingly to do evil, then it is a sin, but really, when it comes to real life situatuions that, either way you look at it, are good intentions, then all we are practicing is our gift of free will. It's not really that hard to figure out, do I want to date this girl, well no, not my type, but I would like to date this other girl. But in reality,. how do we know which one God choose for us?? we don't, therefore that act of free will is not a sin. Again, if we knew who we were supposed to be with, and where we're supposed to be at in life, then all this would be predestination, and not free will.