The Gita's answer to Paul's question in Romans 7:15

At some point every spiritual seeker wonders what makes us do things we know are not good for us, even when we sincerely want to do otherwise.  What compels us to sin as if by the force of nature even when we realize that doing the right thing would yield a far better result? It is our restless nature that leads to our desires and that unrelenting unappeasable craving for something new, different, more or better as well as our anger which is the product of our unfulfilled desires.  That is the enemy.  So, the first step is to recognize desire as the sinful one, not you.  Control the thoughts of your restless mind and your attachment to having your senses satisfied and you will destroy those desires and realize your true inner soul-self as being the real “you.”

A famous passage from the Gita

It is not beneficial to try to force yourself to suppress your natural tendencies.  It is far better to follow your innate calling, however imperfectly than it is to try to live the way someone else thinks you should.  Even if following someone else’s way of life would lead to more accomplishments, in the end, at the moment of death, it will be better to die having lived your own life rather than someone else’s.

Non-attachment doesn't mean you don't enjoy life

Even someone who realizes the wisdom of remaining unattached will follow his or her own natural tendencies, just like anyone else.  It is natural to be attracted to pleasure and avoid pain.  Being non-attached does not mean that you don’t enjoy the pleasure that comes your way or that you don’t act to reduce the unpleasant aspects of your life. Just don’t let yourself become dominated by their influence.  If you remain unattached you will be free from disappointment when pleasure inevitably fades and just as free from any negative impact that the equally inevitable presence of discomfort brings.  Those who don’t live by these teachings are left to suffer their own fate. They don’t understand the true nature of the reality that surrounds them.

"You" shouldn't take credit for what you do, or blame yourself for what you can't do

If you dedicate all your efforts to benefiting those around you, without egotism and expectations, free from worry, your mind can rest peacefully and it will identify with the image of God within.  When the mind is deluded by the ego a person thinks “I am the one responsible for doing that!”  The truth is, your actions are completely a function of your God-given qualities combined with the influence of your upbringing, the society around you and the era in which you live.  You haven’t done anything other than what your talent allows and what you have been taught by others.  A person who realizes this can easily remain unattached to whatever the natural outcome of his or her actions are. But a person of realization should not try to convince someone who is still deluded by their attachment to their physical body of this fact.  It will only bewilder them.   Those who are still identified with satisfying their senses (which are subject to natural fluctuations) cling to the results of their activities for their happiness. They are doomed to suffer.

Wise people are a role model for the rest of us

Even when you reach the state of mind where you feel like you have nothing to gain or lose by your actions, you must continue to do what you have to do with integrity.  Whatever a great person does will be copied by others and used as a standard for their own behavior.  Always do what you have to do without attachment because if you were to cease to act others would follow your example. An enlightened person does everything with the same zeal that an unenlightened person does but he or she does so without attachment, thus serving as a role model for others.  A wise person will not disturb the mind of those who are still attached to the fruits of their actions, but by continuously performing their own actions skillfully, without attachment, the wise person influences and inspires all those nearby.

Don't depend on external circumstances for your happiness

Anyone who chooses to live life attached to the pleasure or pain of the mind and body lives in vain.  The person who truly identifies with the image of God within, who is fully satisfied with doing the right things for its own sake, that person will have nothing else to do to become satisfied.  He or she is not disappointed with the lack of personal gain nor does that person fail to act because of the fear of losing something.  That person is not dependent on anyone or anything for their satisfaction.

Becoming free from your karma

Actions that you perform with attachment to getting the results you want are bound to have further implications in your life.  Any selfless act done without attachment will free you from the effects it can have later on.  By sacrificing the desire to have the results of your actions benefit yourself, you will find that you get everything you want out of the experience itself.  Whoever takes the rewards for their actions without giving anything back is like a thief.  Anyone who acts only for selfish gain creates the same things sins do in their life.