"Blessed be the God and Father of our Lord Jesus Christ! According to his great mercy, he has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead, to an inheritance that is imperishable, undefiled, and unfading, kept in heaven for you, who by God's power are being guarded by faith for a salvation that is ready to be revealed in the last time. In this you rejoice, though now for a little while, if necessary, you have been grieved by various trials, so that the tested genuineness of your faith--more precious than gold that perishes though it is tested by fire--may be found to result in praise and glory and honor at the revelation of Jesus Christ. Though you have not seen him you love him. Though you do not now see him, you believe in him and rejoice with joy that is inexpressible and filled with glory, obtaining the outcome of your faith, the salvation of your souls." (1 Peter 1:3-9 ESV)
Socrates riled up the Athenians, in part, by challenging their basis for ethics. In the dialogue Euthyphro, Socrates asks the question, "Is a thing good because it is loved by the gods, or do the gods love it because it is good?" He goes on to further ask, "What if one god loved a thing, but another did not?" In essence, Socrates revealed to the Athenians that their basis for ethics, doing good because it pleased the gods, was really no foundation at all, because it did not answer the question, "What is good?"
This method of undermining the Christian basis for ethics doesn't work like it did in Athens because we do not have many gods, but one God. Therefore it is impossible that what one god should love another should despise, for we have but one God. What God loves, therefore, is good. There can be no question of which came first, the love of God or the goodness of the thing, for God is the first and was before all things. Christians thus have no issues with basing our ethical foundation on what God loves.
But, even if we know the right thing, why should we do that which we no do is right? James notes that he who knows the right thing to do and does not do it sins (James 4:17). But, so what? What does it matter if we sin? What does it matter if we do right? We must have a reason, a foundation, for actually doing good.
Augustine of Hippo (St. Augustine), in book 2 of his Confessions, tells of a time when he stole some pears amongst a group of friends. Augustine notes that he knew what was good and would likely have not stolen those pears if he had not been around others encouraging him to steal, but he still acknowledges that he did what was wrong despite knowing better. This raises the question that all of us must ask, "Why should we do what is right, when what is right is not always what we want to do?"
1 Peter 1:3-9 gives us the answer to that question. In 1 Peter we come to understand why we ought to do what is right, and what the real foundation of good is. We understand the value of good works from what Peter tells us of our own future. Consider what Peter says here, "[your] inheritance [is] imperishable, undefiled, and unfading, kept in heaven for you." The promise of Scripture is that we will have an eternal inheritance, which will never fade, never be blemished, and can never be defiled.
You see, the basis for Christian ethics is the eternal reality of our future inheritance. This is a matter of guarantee, having been promised by God, and therefore it cannot be revoked. Our inheritance is a permanent, eternal dwelling with Christ, the one we love. And it is because we love him and will be with him forever that we strive to please him now in our actions, our attitudes, and our thoughts. It is our nature to strive to please the one we love, and it is because of the great love we have for Christ, a love given to us by him who first loved us, that we desire to do what is good. For what pleases Christ is what is good, and as we desire to please him we do that which is good.
You see, for the Christian, that which is good has eternal consequences. Here is the real strength of Christian ethics. We do not strive for what is good for an hour, a day, or a year. Rather, that which is good is, for the Christian, eternally good. This does not mean that what is good in one situation is good in every situation, rather that when we do what is good we do an act of eternal significance. We see this in Peter's declaration that our faith will result in praise and glory at the revelation of Jesus Christ. That which is good is that which is pleasing to Christ, and that which is pleasing is that which is done in faith, in love of him, so that it is the act of faith that results in the praise of Christ at his revelation, which praise will never end, so that every act of faith has the eternal implication of bringing glory to our Lord and Savior.
Christianity thus answers the question of what is right and good in a way which no secular system can answer, by showing us that our actions are not good for a moment, a year, or even a lifetime or a hundred lifetimes. Our acts are eternally good, never ceasing to have value. This is the limit of the secular world, arguing that what we do helps another human, or a thousand humans, all of whom shall die and one day cease to be. Every good act, from a secular perspective, one day will cease to have any meaning. We will die, our children, and their children, and so on for as many generations as mankind continues, until one day the sun burns out, the earth grows cold and every good work, every kindness, every act of charity and love comes to mean nothing. In the cold blackness of the eternal fate of our reality no good work is rewarded, and no wickedness is punished, for all end up the same. This is the secular world view, and it cannot sustain us in doing what is good and right.
But, for the Christian, we know that God is eternal. Every good work is forever remembered by him. And as he is eternal, thus outside of time, every good work is eternally so, known by him in the moment it was done, thus being eternally good. We shall live forever rejoicing in the good that was done, never losing the value of the kindness of charity and the beauty of love. We may live in a world that will one day pass away under the judgment of God, but we live for a world that will be eternal, never ceasing. And it is 1 Peter that shows us the basis for why we do good in a world passing away, because of the inheritance to come, of a world unending, dwelling with a God we love more than the temporary pains that come in this fleeting life.
Live to do good. Love your God. Rejoice in the salvation that has been purchased at such a great cost. Understand that your good acts are not in vain, and though evil may be repaid in this world, our God has stored up great and wondrous treasures for those he loves. This is the greatness of the gospel of Christ; it gives reason for life, reason for hope, and a reason to do good in the midst of an evil time and fallen world.