Alyssa from Lancaster asks, “Pastor John, I grew up in a wonderful Christian home where the gospel was lived out before me every day, and I trusted Christ as my Savior in my youth. However, around the age of fourteen, I began to wrestle with many questions about the Christian faith. Throughout the seven years since then, I have spent countless hours studying the Christian worldview and apologetics, as well as other worldviews. I see no lack of evidence for the Christian faith, but my mind always comes up with more questions that don’t seem to have satisfactory answers in order for me to feel honest about believing the things in God’s word. At the end of the day, I don’t understand how I can ever know any truth for sure, since I will never be able to collect all the facts about anything. How can we, as finite humans, be certain that we have found the truth when we are limited by our own humanity?”
That is so good. The issues of knowing and certainty and assurance are so, so relevant. Everybody deals with these things at some point. So, as I understand it, here is the key, final, decisive question: How can we, as finite humans, be certain that we have found the truth when we are limited in our own humanity? We are finite, but we want certainty, and they don’t seem to go together.
God’s Desire for Our Assurance
Before I answer the question — and I will give an answer that I think is biblical — let me put some biblical truth in front of us here. The first is to be sure that we are aware that God really does want us to have full assurance of his reality and the truth of the gospel — full assurance, certainty, deep, strong, unshakable conviction. He did not design a world where that is impossible for fallen, finite people:
1 John 5:13: “I write these things to you who believe in the Son of God that you may know that you have eternal life.”
John 7:17: “If anyone’s will is to do God’s will, he will know whether the teaching is from God.”
Hebrews 6:11: “We desire each one of you to show the same earnestness to have the full assurance of hope until the end.”
Colossians 2:2: “How great a struggle I have [of them] . . . that their hearts may be encouraged . . . to reach all the riches of full assurance of understanding.”
Romans 1:20–21: “For [God’s] invisible attributes . . . have been clearly perceived, ever since the creation of the world, in the things that have been made. So they are without excuse. For although they knew God” — they knew God — “they did not honor him as God.”
So God did not design the world and the way of salvation and the process of revelation and the nature of the Bible and the work of the Holy Spirit, he didn't design any of those so we would only have good probability judgments about the truth. He did not intend for us to cross our fingers. I saw a woman sitting in the final of the World Cup. They showed, I think, a woman from Argentina, and she just had her fingers crossed in the last minutes. I thought: That is not the way we approach the final judgment with our fingers crossed. Oh, I wonder if I am going to make it at the last day. That is a tragedy if Christians have to die with their fingers crossed. He didn’t intend us to leap into the dark either.
Two Levels of Certainty
So Alyssa is right in asking the question how. That is the right question: how — how, not if —can we as finite human beings be certain that we have found the truth?
1. Trustworthiness is more than the sum of trustworthy evidences.
And the answer, I think, comes at two levels. Warranted certainty of another person’s trustworthiness is more than the sum of the empirical evidences that he is trustworthy. I know that is a little bit of a complicated sentence. I mean, warranted certainty is more than adding up, one, two, three, four, five — I have got six evidences that he is trustworthy. Now I can be certain. That never works. It never works. Because you can always ask another question, right?
“It is not a guess or a mere deduction by fallible logic. It is a gift of God through the ordinary means of knowing the gospel.”
I trust my wife, that she is faithful to me. I could give evidences from experience — lots of them. But at the end, there would always be doubt, wouldn’t there, if it were just the list of evidences, because she could be tricking me somehow. Just like Alyssa says about her own knowledge of God. She studies. She asks questions. She gets answers, and there always seems to be another question because she is finite, just like I am fallible about Noёl.
In fact, I have zero doubt that Noël is faithful to me. She is. I never lose a moment’s sleep over it. So experientially, I have a working certainty, and it is more than the sum of the parts. It is a personal assurance that comes from a personal encounter. Knowing her creates something which is in, yes, the evidences, and then goes subjectively beyond the evidences. And I think we can have that kind of personal knowledge of Jesus — exposure to his self-revelation in the Bible. The more you get to know him, the surer you are that he is reliable.
2. God grants us eyes to see.
Here is the other level: God does not give us certainty by whispering in our ear that we are true, or he is true, but he does give us certainty. It is a gift of God. He does it by opening our eyes, the eyes of our hearts, to see the real self-evidencing glory of God in the gospel. And I get that partly from Ephesians 1, but mainly from 2 Corinthians 4:4, which goes like this: “The god of this world has blinded the minds of unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God.” And verse 6 continues, “For God, who said, ‘Let light shine out of darkness,’ has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ.”
“The more you get to know Jesus, the surer you are that he is reliable.”
So, in both cases, light is imparted by God. It is the light of gospel or the light of knowledge. And, more specifically, it is the knowledge of glory or the gospel of glory. So there is a revelation of the glory of God, the glory of Christ, in the gospel, in the knowledge of the historical revelation given in the Bible, that is self-authenticating. There is a divine and supernatural light — that is the phrase of Jonathan Edwards —imparted to the soul by the work of God, which is a real seeing.
It is a real seeing. That is really crucial. It is not irrational. It is a real seeing of what is really there. It is not a guess or a mere deduction by fallible logic. It is a gift of God through the ordinary means of knowing the gospel. And we should pray for this. So that would be my closing exhortation is that we would pray — that Alyssa would pray — “Open my eyes to see this wonderful, self- authenticating light of glory in your word.”