Where do we find in the Bible that it is our conscience that speaks, guides and controls us?

If we believe in God, it results in the moral responsibility to do things that are good and we feel guilty when we fail. In Romans 2:15, Paul says that “their conscience also bears witness, and their conflicting thoughts accuse or even excuse them.” However, Jesus does not say that we should be guided solely by our conscience, but rather that we should obey his commandments. He says,

By this is my Father glorified, that you bear much fruit and so prove to be my disciples. As the Father has loved me, so have I loved you. Abide in my love. If you keep my commandments, you will abide in my love, just as I have kept my Father’s commandments and abide in his love. (John 15:8-10)

In Galatians 5:22, Paul elaborates on the fruit that the followers of Christ should develop in their lives. “The fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control.” So, it is good to develop a conscience that is consistent with our efforts to follow the example of the Lord Jesus Christ.