Heidelberg Catechism Q/A 87 explicitly affirms the biblical teaching regarding the necessity of repentance. It says,
Q.87. Can those be saved who do not turn to God from their ungrateful and unrepentant ways? A. By no means. Scripture tells us that no unchaste person, no idolater, adulterer, thief, no covetous person, no drunkard, slanderer, robber, or the like will inherit the kingdom of God.
Can anyone be saved without repentance? That is the question. And the answer is clear and to the point – “By no means.”
The Westminster Confession of Faith similarly states,
“Although repentance be not to be rested in, as any satisfaction for sin, or any cause of the pardon thereof, which is the act of God’s free grace in Christ; yet it is of such necessity to all sinners, that none may expect pardon without it.” (15.3)
And so while we must be careful to maintain that we are not saved by means of our repentance (as if we could somehow earn or merit our forgiveness and salvation by it), yet we must also maintain that we are not saved without it. As the Westminster Confession of Faith (above) puts it, “none may expect pardon without it.”
In his commentary on the catechism Zacharias Ursinus (the primary author of the catechism itself) explains:
“This question [i.e. Q/A 87] naturally grows out of the preceding one [i.e. Q/A 86, on good works]; for since good works are the fruits of our regeneration – since they are the expression of our thankfulness to God, and the evidences of true faith; and since none are saved but those in whom these things are found; it follows, on the other hand, that evil works are the fruits of the flesh – that they are manifestations of ingratitude, and evidences of unbelief, so that no one that continues to produce them can be saved.” (p.467)
Repentance (i.e. turning from evil works unto God), like good works, is ‘the fruit of our regeneration’ and ‘evidence of true faith.’ And so, conversely, the lack of repentance and good works, and the continuing on in the practice of evil works are then “the fruits of the flesh” and “evidences of unbelief.”
In 1 John 3:10 the Apostle John writes,
“By this it is evident who are the children of God, and who are the children of the devil: whoever does not practice righteousness is not of God, nor is the one who does not love his brother.” (ESV)
On what basis does the Heidelberg Catechism teach these things? Notice that Q/A 87 points directly to the clear and explicit teaching of Scripture on this subject when it says, “Scripture tells us that no unchaste person, no idolater, adulterer, thief, no covetous person, no drunkard, slanderer, robber, or the like will inherit the kingdom of God.”
Here the catechism echoes Paul’s words to the church in Corinth:
“Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God. And such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.” (1 Corinthians 6:9–11, ESV)
The “unrighteous” here are those who continue in the ongoing practice of sins like the ones Paul goes on to list there (not that his list is exhaustive by any means).
He even adds, “Do not be deceived.” Is there not a constant temptation to deception in these very matters? That was certainly the case in Paul’s day. (Or do we really think that we are so much better than the church in Corinth?)
Here once again we see the pastoral wisdom involved in the Heidelberg Catechism, as it constantly points us back to the Scriptures as the foundation for all that it teaches us. And not only that, but it also makes us wrestle with these things in such a way that as we ask and answer questions like this one, we must ask ourselves whether or not we truly see the fruits of regeneration and evidences of a true and living faith in our lives.
This, like the rest of the doctrine taught in the Heidelberg Catechism, is something that is necessary for us to know in order that we may live and die in the joy of the comfort that is ours only in Jesus Christ (Q/A 2).