Benjamin Keach's Catechism, Q3: How Do We Know?

Q. 3. How do we know there is a God?

A. The light of nature in man, and the works of God, plainly declare that there is a God; but His Word and Spirit only, do effectually reveal Him unto us for our salvation. (Rom. 1:18-20; Psalm 19:1,2; 2 Tim. 3:15; 1 Cor. 1:21-24; 1 Cor. 2:9,10)

Scripture Proofs

For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who by their unrighteousness suppress the truth. For what can be known about God is plain to them, because God has shown it to them. For his invisible attributes, namely, his eternal power and divine nature, have been clearly perceived, ever since the creation of the world, in the things that have been made. So they are without excuse. (Rom. 1:18-20)

The heavens declare the glory of God,
     and the sky above proclaims his handiwork.
Day to day pours out speech,
     and night to night reveals knowledge. (Ps. 19:1, 2)

...and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. (2 Tim. 3:15)

For since, in the wisdom of God, the world did not know God through wisdom, it pleased God through the folly of what we preach to save those who believe. For Jews demand signs and Greeks seek wisdom, but we preach Christ crucified, a stumbling block to Jews and folly to Gentiles, but to those who are called, both Jews and Greeks, Christ the power of God and the wisdom of God. (1 Cor. 1:21-24)

But, as it is written,

“What no eye has seen, nor ear heard,
      nor the heart of man imagined,
what God has prepared for those who love him”—

these things God has revealed to us through the Spirit. For the Spirit searches everything, even the depths of God. (1 Cor. 2:9, 10)

I actually addressed this question not that long ago in a way. Granted, my argument was more philosophical than anything else, but it still was my attempt to give an answer to the question: How do we know there is a God? I think, since I already recently wrote about it, I'm not going to give the same argument a second time; if you're interested, go back and read the post I linked to. My purpose in this series isn't really to discuss purely philosophical ideas or arguments anyway, but rather to examine the questions of this catechism in light of the Scriptures and see how it stands up. This question, in my opinion, stands up just fine.

The first two verses address the first part of the answer: "The light of nature in man, and the works of God, plainly declare that there is a God." I think that addresses a few things: first off, as Keach himself gives Romans 1:18-20 as a proof of what he states, he clearly means that nature is proof of God's existence. And indeed, "the heavens declare the glory of God" (Ps. 19:1) and "his righteousness" (Ps 50:6). Not only that, but "day to day pours out speech, and night to night reveals knowledge" (v. 2). The 1599 Geneva Bible gives this commentary on the second verse: "The continual success of the day and the night is sufficient to declare God’s power and goodness." Basically, that day and night come and go testify to God's goodness and power. We are surrounded by testimony of his existence all the time!

But the words "in man" remind me of another passage: "When Gentiles, who do not have the law, by nature do what the law requires, they are a law to themselves, even though they do not have the law. They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them" (Rom. 2:14-15). God has literally written his law, the absolute standard of right and wrong, on the hearts of all people. When people declare that something is morally wrong, they are appealing to some standard of good and evil. That standard, and that we know that standard, is proof of God's existence. People skew and ignore that standard all the time, however; men "by their unrighteousness suppress the truth" (Rom. 1:18). Men suppress it. They still have it, but they pretend they don't. They also suppress the truth of God's existence proclaimed in nature; when they see it, even though it clearly testifies of him, they act as if it doesn't and even delude themselves into believing it doesn't.

So how can the truth penetrate the veil? Keach answers, "His Word and Spirit only, do effectually reveal Him unto us for our salvation." The key word here is "only;" God's Word and Spirit are the only things that reveal God in a saving way to people. Fallen human reason cannot get us to God by itself; our bias towards evil keeps us away from that. Also, the idea that our Savior is someone who was killed on a cross is "a stumbling block to Jews and folly to Gentiles" (1 Cor. 1:23). That's not to say reason has no place in discussing salvation, but rather that without God's Spirit moving, it won't save anyone. But salvation, which "no eye has seen, nor ear heard, nor the heart of man imagined, what God has prepared for those who love him . . . God has revealed to us through the Spirit" (1 Cor 2:9, 10). And through the Spirit, we can understand "the sacred writings, which are able to make you wise for salvation through faith in Jesus Christ" (2 Tim. 3:15).

Even though we are surrounded by evidence of God's existence day by day, we in our wickedness suppress the truth and pretend it does not exist. Only God, through the Holy Spirit and the Scriptures, can open our eyes and bring the truth to light.

To read the full catechism, click here.