Is it love or is it the Law that guides us Christians in our day-to-day living?
I've been reading quite a bit from Martin Luther's writings lately and he would say salvation is of course by faith, but that the Law is still to be used as a guide for holy living. But, he says, when one feels the guilt from not being able to keep the Law, we should quickly remember the Gospel and discard, rather than entertain, any thoughts or feelings of condemnation. Luther also zealously argued the need for the Law in converting unbelievers, Jew or Gentile. He said it was necessary that people see their own sin before they could come to Christ for justification.
However, I do not see that in the scripture. I see Paul preaching only Christ and faith to the majority of his Gentile audience, who were unacquainted with the Law. I also see Paul, in his letter to Timothy, explain that it is Christ's love that restrains us from evil works. The scripture from Romans immediately comes to mind where Paul says "Sin shall not have dominion over you, for you are not under law but under grace."
In fact, Paul says the power of sin is in the Law, and that the Law can only serve to incite sin within the human race and thus show mankind's need for the Savior.
So, it seems right to me, that if we would be free from sin, we should continually renew our minds with the Gospel so as to stir up faith within our hearts, and our hearts being purified by faith, we receive the power to abstain from every kind of sin.
This is not, however, automatic. There is discipline to be had, but the motive for our discipline has changed entirely under the new paradigm the Gospel gives us. The motive for discipline now comes from our love of Christ, because, as the scripture says, he first loved us.
So then, the requirement for a Christian, if they are to remain free from sin, is the renewal of his or her mind that comes from hearing the Gospel afresh, daily. The only two remedies for sin that a Christian receives from God are these: the Gospel and the Holy Spirit. The Christian is not given the Law as a remedy for sin. The Law is for those outside the faith, holding them under the condemnation of God. It would make no sense for a Christian to continue to utilize the Law when the Law has already accomplished in him the work for which it was sent. That is, to lead them to Christ. Now that faith has come into a Christian's heart, there ends his partnership with the Law. He is entirely dead to the Law and it's requirements.