Now since God’s majesty in itself far outstrips the capacity of human understanding and cannot even be comprehended by it at all, it is fitting for us to adore rather than to investigate its loftiness, lest we be utterly overwhelmed by such great splendor. Accordingly, we are to search out and trace God in his works, which are called in the Scriptures “the reflection of things invisible,” because they represent to us what otherwise we could not see of the Lord. This is not something that keeps our minds in suspense with vain and empty speculations, but something that is beneficent for us to know and which begets, nourishes, and strengthens perfect godliness in us, that is, faith joined with fear. For in this universe of things we contemplate the immortality of our God, from which flow the beginning and origin of everything; we contemplate his power which both framed this great mass and now sustains it; we contemplate his wisdom which composed in definite order this very great and confused variety and everlastingly governs it; we contemplate his goodness, itself the cause that these things were created and now continue to exist; we contemplate his righteousness marvelously preferring itself to defend the godly but to take vengeance of the ungodly; we contemplate his mercy which, to call us back to repentance, tolerates our iniquities with great gentleness.

From all this we ought abundantly to have been taught — as much as is sufficient for us — what God is like, but for the fact that our sluggishness was blinded by such great light. And not only do we sin out of blindness alone, but such is our perversity that in reckoning God’s works, there is nothing it does not interpret badly and wrongheadedly, and it turns completely upside down the whole heavenly wisdom which clearly shines in them. Therefore, we must come to God’s Word, where God is duly described to us from his works, while the works themselves are reckoned not from the depravity of our judgment but the eternal rule of truth. From this, therefore, we learn that God is for us the sole and eternal source of all life, righteousness, wisdom, power, goodness, and mercy. As all good flows, without any exception, from him, so ought all praise deservedly to return to him. And even if all these things appear most clearly in each part of heaven and earth, yet we at last comprehend their real goal, value, and true meaning for us only when we descend into ourselves and ponder in what ways the Lord reveals his life, wisdom, and power in us, and exercises toward us his righteousness, goodness, and mercy.

“3. What We Must Know of God” in Calvin’s Catechism (1538)