The Bible teaches that those who have once believed in Christ are secure forever in their salvation. This does not mean that God does not care about the remaining sin in His children. The Bible also teaches that our heavenly Father is displeased with His people’s disobedience and will chastise them for it, determined to lead them away sin. This distinction is presented beautifully in Psalm 89:30–33:
If his sons forsake My law and do not walk in My judgments, if they break My statutes and do not keep My commandments, then I will punish their transgression with the rod, and their iniquity with stripes. Nevertheless, My lovingkindness I will not utterly take from him, nor allow My faithfulness to fail.
Huguenot theologian Jean Daillé’s comment on this passage is to the point:
God here says two things: first, that he will chastise them, next, that he will not, on that account, cast them out of his covenant. O wonderful, tempering fo the kidness and severity of God! In which he finds his own glory, and believers their safety!
God will not break His covenant with His people, but He does interact with them, delighting in their obedience and chastising their disobedience.
Oftentimes, we struggle to find the right balance between saying that our obedience does not affect our standing before God and saying that obedience to the law is important. If we would listen carefully to our Westminster Standards on this matter, I believe we would find that it has captured the biblical balance beautifully.
For example, consider Chapter 17, “On the Perseverance of the Saints.” Section 1 states:
They, whom God hath accepted in his Beloved, effectually called, and sanctified by his Spirit, can neither totally nor finally fall away from the state of grace, but shall certainly persevere therein to the end, and be eternally saved.
At the same time, the Confession is clear that obedience is very important. Here is how the Confession explains it:
Nevertheless, they may, through the temptations of Satan and of the world, the prevalency of corruption remaining in them, and the neglect of the means of their preservation, fall into grievous sins; and, for a time, continue therein: whereby they incur God’s displeasure, and grieve his Holy Spirit, come to be deprived of some measure of their graces and comforts, have their hearts hardened, and their consciences wounded; hurt and scandalize others, and bring temporal judgments upon themselves.
You will find the same sorts of statements in Chapters 11:1, 5; 15:3; 16:2, 5; 18:2, 4; 19:6; 20:1. Our Confession of Faith has captured a remarkable balance between antinomianism and legalism that takes into account the full scope of biblical teaching.