Romans 10:2

2.For I bear to them a testimony, etc. This was intended to secure credit to his love. There was indeed a just cause why he should regard them with compassion rather than hatred, since he perceived that they had fallen only through ignorance, and not through malignancy of mind, and especially as he saw that they were not led except by some regard for God to persecute the kingdom of Christ. Let us hence learn where our good intentions may guide us, if we yield to them. It is commonly thought a good and a very fit excuse, when he who is reproved pretends that he meant no harm. And this pretext is held good by many at this day, so that they apply not their minds to find out the truth of God, because they think that whatever they do amiss through ignorance, without any designed maliciousness, but with good intention, is excusable. But no one of us would excuse the Jews for having crucified Christ, for having cruelly raged against the Apostles, and for having attempted to destroy and extinguish the gospel; and yet they had the same defense as that in which we confidently glory. Away then with these vain evasions as to good intention; if we seek God sincerely, let us follow the way by which alone we can come to him. For it is better, as [Augustine ] says, even to go limping in the right way than to run with all our might out of the way. If we would be really religious, let us remember that what Lactantius teaches is true, that true religion is alone that which is connected with the word of God. (320)

And further, since we see that they perish, who with good intention wander in darkness, let us bear in mind, that we are worthy of thousand deaths, if after having been illuminated by God, we wander knowingly and willfully from the right way.