Is It a Sin to Act Against Your Conscience?

Martin Luther said, “To act against conscience is neither right nor safe.” Was he right?
R. C. Sproul answers:

Here we must tread carefully lest we slice our toes on the ethical razor’s edge.
If the conscience can be misinformed or distorted, why should we not act against it?
Should we follow our consciences into sin?
Here we have a dilemma of the double-jeopardy sort.
If we follow our consciences into sin, we are guilty of sin inasmuch as we are required to have our consciences rightly informed by the Word of God.
However, if we act against our consciences, we are also guilty of sin. The sin may not be located in what we do but rather in the fact that we commit an act we believe to be evil. Here the biblical principle of Romans 14:23 comes into play: “Whatever does not proceed from faith is sin.” For example, if a person is taught and comes to believe that wearing lipstick is a sin and then wears lipstick, that person is sinning. The sin resides not in the lipstick but in the intent to act against what one believes to be the command of God.
The dilemma of double jeopardy demands that we diligently strive to bring our consciences into harmony with the mind of Christ lest a carnal conscience lead us into disobedience. We require a redeemed conscience, a conscience of the spirit rather than the flesh.
The manipulation of conscience can be a destructive force within the Christian community.
Legalists are often masters of guilt manipulation, while antinomians master the art of quiet denial.
The conscience is a delicate instrument that must be respected. One who seeks to influence the consciences of others carries a heavy responsibility to maintain the integrity of the other person’s own personality as crafted by God. When we impose false guilt on others, we paralyze our neighbors, binding them in chains where God has left them free. When we urge false innocence, we contribute to their delinquency, exposing them to the judgment of God.

You can read the whole post here, excerpted from Sproul’s booklet How Should I Live in This World?  
Justin Taylor