Therefore let us stop passing judgment on one another. Instead, make up your mind not to put any stumbling block or obstacle in the way of a brother or sister. I am convinced, being fully persuaded in the Lord Jesus, that nothing is unclean in itself. But if anyone regards something as unclean, then for that person it is unclean. If your brother or sister is distressed because of what you eat, you are no longer acting in love. Do not by your eating destroy your brother or sister for whom Christ died. Therefore do not let what you know is good be spoken of as evil. For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit, because anyone who serves Christ in this way is pleasing to God and receives human approval. Let us therefore make every effort to do what leads to peace and to mutual edification. Do not destroy the work of God for the sake of food. All food is clean, but it is wrong for a person to eat anything that causes someone else to stumble. It is better not to eat meat or drink wine or to do anything else that will cause your brother or sister to fall. So whatever you believe about these things keep between yourself and God. Blessed are those who do not condemn themselves by what they approve. But those who have doubts are condemned if they eat, because their eating is not from faith; and everything that does not come from faith is sin.
—Romans 14:13-23 (TNIV)
Here we have another textbook example of faith leading to right works. Paul continues to talk to the strong Christians about how to behave themselves around “weaker” Christians, those whose faith did not yet allow them to partake of the wonderful freedom that is in Christ, at least in dietary customs and habits.
“Don’t offend your weaker brothers and sisters,” says Paul. “Why? Because this is the Lord’s will for you. Remember that you were bought at a terrible price. So were your weaker brothers and sisters in Christ. Remember you don’t have a snowflake’s chance on water to live forever in God’s direct Presence without the blood of Christ shed for you. You didn’t earn it nor do you deserve it. It was God’s wondrous grace and mind-blowing love for you that caused him to give you this great gift in his Son. So act like you believe it. Act because you believe it.”
Could Paul empirically prove any of this? Nope. Nor did he feel the need to do so because empirical proof is not the ruler and arbiter of all things (or of anything for that matter). Empiricism has its place but not in “proving” the work of the cross. That requires faith and faith always manifests itself in works. This doesn’t mean we check our minds or reason at the door (to the contrary, our minds and reason help us to make sense of the content of the Gospel). It simply means we use the right tools for the right contexts.