This is a great statement from the Heidelberg Catechism:
Question 86: Since then we are delivered from our misery, merely of grace, through Christ, without any merit of ours, why must we still do good works?
Answer: Because Christ, having redeemed and delivered us by his blood, also renews us by his Holy Spirit, after his own image; that so we may testify, by the whole of our conduct, our gratitude to God for his blessings, and that he may be praised by us; also, that every one may be assured in himself of his faith, by the fruits thereof; and that, by our godly conversation [lifestyle] others may be gained to Christ.
Note a few things.
First, good works are a means by which we imitate, and thus glorify, Christ. We have been renewed “after his own image,” and doing good works reflects his image, and thus glorifies him. Christ was mighty in word and deed (Luke 24:19), and thus it is essential that we reflect Christ in our actions as well as our words.
Second, note that we are to testify to the greatness of Christ “by the whole of our conduct.” You don’t just testify to the greatness of Christ in words, as critical as that is. You must also testify to his greatness in all of your conduct. You not only may, you must!
Third, our good works are a form of worship. We do them in gratitude to God and out of love for him, and offer them to him in our doing of them. That’s what worship is. And God wants to be worshipped in the whole of our lives (Romans 12:1-2), not just our words. This makes our good works — that is, all the things we do in faith, even tying our shoes — intrinsically meaningful.
Fourth, one result of living wise lives filled with good works is that others will be won to Christ. Good works are not valuable simply as a means to bringing others to faith; they are valuable in themselves (see above points). But they do also have the effect of supporting our testimony to the gospel, and others will come to faith as a result (that’s the meaning of the very odd and hard to understand passage in Ephesians 5:7-14).
So, once again, we see that the Reformed tradition was holistic. The dichotomy between doing good/living wise lives and preaching the gospel does not exist in the theology of the Reformation. The ministry of the word goes to the root, but testifying to the greatness and love of God in our deeds is equally essential.