What is the purpose of the conscience? How does it function? Can it be wrong? In this sermon on Romans 9:1–3 titled “Paul’s Great Concern,” Dr. Martyn Lloyd-Jones dissects the phrases that Paul uses to show how his conscience testifies to the truth of Scripture. This, says Dr. Lloyd-Jones, must first be considered, both the statement and the terms in which he says them. Then the reader can go on to consider the lessons and conclusions. Paul is attesting that his own conscience is a witness that what he is saying is true. Dr. Lloyd-Jones points out that a person’s conscience is independent of the person. The extent to which the conscience is saturated with Scripture determines the extent to which one can depend on their conscience. Additionally, Dr. Lloyd-Jones warns never to speak against it or condemn it on the basis of personal opinion. The conscience is enlightened by the Holy Spirit in the Christian and it is used by the Holy Spirit to convict. Paul then says how grieved he is over the Jews and their condition, wishing he himself could take their place. Dr. Lloyd-Jones begins to ask why Paul is making these types of statements and states that Paul is doing this because he is eager to clear the charges that were against him.

http://www.mljtrust.org/sermons/pauls-great-concern/