Sin is one of the most misunderstood concepts today. All too often it is tied to guilt and fear which has the potential to be psychologically disturbing. "If you don't do A, B will happen to you." Surely this is not encouragement to avoid sin but rather motivation to conceal sin.
In the New Testament, the Greek word for sin is hamartia, which literally means 'to miss the mark'. Think of an archer pulling on the bowstring to point the arrow at the target. Think of the archer's body; every muscle aligned with precision, eyes focussed on the target, coordinated breathing, stillness, and full concentration. To hit the target the first time, and every time after that, is expecting a lot.
Let's take a look at the word 'sin' in this bible text.
"Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained." John 20:22f
If we start with the Greek word for 'any,' which is tis; it is an interrogative pronoun used in order to ask a question: who, which, what? It doesn't necessarily refer to others, it can refer to ourselves by applying it in this way: 'If you forgive the sins of yourself? they are forgiven;'.
Forgive is aphiemi made up of two words; apo and eimi. Apo means separating the part from the whole, or distancing ourselves; eimi means 'to be', as we might say, "I just am." This suggests a state of harmony and balance, and a position of recognition (not necessarily acceptance).
Retained is krateo which means to have power, to be powerful. Whenever we want power, we usually have the wrong motive. We enter into a state of compensation rather than just being with whatever is happening.
A better way of understanding sin is to see it as a state of non-perfection, which has the possibility of becoming perfection. Then sin becomes something constructive, part of our goal. With this attitude, we have the courage to keep pulling on the bowstring, working on our aim and our poise.
When we have developed a certain level of skill we are able to see how we have underperformed. When it comes to sin, this takes courage. Usually we are inclined to make excuses for missing the mark; it was someone else's fault. Then we engage in the power of retaining sin, not the recognition required for forgiving sin.
If we are going to hit the mark, we need to work out what the mark is. What target are we, as human beings, aiming for? Surely is it love, the New Commandment: Love one another as I have loved you. John 13:34
This love understands; it has the right perspective. It is a love that recognizes the effort involved in honing the archer's aim. We become objective and in this way, we stand in the other person's shoes and see, not their failure, but how, step by step, they sharpen their aim. We also apply these same principle to ourselves.
We could also say that we sin when we don't make an effort to understand sin. Without this understanding, we perpetuate sin. Our task is to aim the bow by recognizing the right way and the wrong way. None else can do this for us, not any law of government or religion, but only our own understanding of who we are as human beings and where we stand in the universe. There is an ancient saying, "Man, know yourself!" and as we work towards knowing ourselves we become much more aware of our motives. The true meaning of sin gives us the courage to objectively recognize how we miss the mark and work on perfecting our aim.