The apostle Paul exhorts Christians to “walk by faith and not by sight” (2 Corinthians 5:7). What we see here is a contrast between truth and perception—what we know and believe to be true and what we perceive to be true. This is where the Christian struggle with a lack of faith finds its basis. The main reason why so many Christians struggle with a lack of faith is that we follow our perceptions of what is true rather than what we know to be true by faith.
Perhaps before going any further it may be helpful to come up with a working definition of faith. Faith, contrary to popular opinion, is not “belief without proof.” This is the definition that many skeptics give for faith. This definition reduces faith to mere fideism—i.e., “I believe despite what the evidence tells me.” Skeptics are right to reject this concept of faith, and Christians should reject it, too. Faith is not belief without proof or belief despite the evidence; rather, faith is a complete trust or confidence in someone or something. That trust or confidence we have in someone is built up over time as he proves himself faithful time and time again.
Christianity is a faith-based religion. It is based on faith in God and in His Son, Jesus Christ. God has provided us with His Word, the Holy Bible, as a testimony of His faithfulness to His people all throughout history. In its bare essentials, Christianity is faith in the person and work of Jesus Christ. Jesus Christ claimed to be the promised Messiah and the Son of God. His life was one of perfect righteousness according to the revealed Law of God, His death was an atoning sacrifice for the sins of His people, and He was raised to life three days after His death. When we place our faith and trust in Christ alone for our salvation, God takes our sin and places it on the cross of Christ and awards us, by grace, with the perfect righteousness of Christ. That, in a nutshell, is the Christian message. As Christians, we are called to believe this message and live in light of it.
Despite this, Christians still struggle with believing the biblical account because it doesn’t match up with our perception of reality. We may believe that Jesus was a real person, we may believe that He died by crucifixion at the hand of the Romans, we may even believe that He led a perfect life according to God’s Law, but we don’t “see” how faith in Christ makes us righteous before God. We can’t “see” Jesus atoning for our sins. We can’t “see” or “perceive” any of the great truths of Christianity, and, therefore, we struggle with lack of faith. As a result of this lack of perception, our lives often do not reflect the fact that we really believe what we claim to believe.
There are many reasons for this phenomenon among Christians. The main reason we struggle with faith is that we don’t truly know the God in whom we profess to have faith. In our daily lives, we don’t trust complete strangers. The more intimately we know someone and the more time we have had to see him “in action,” the more likely we are to believe what he says. But, if God is essentially a stranger to us, we are less likely to believe what He has said in His Word. The only cure for this is to spend more time in God’s Word getting to know Him.
The world, the flesh, and the devil often distract us. By “the world” is meant the accepted “wisdom” of the unbelieving world and the culture in which we find ourselves. For those of us living in Europe and North America, that dominant worldview is naturalism, materialism, skepticism, and atheism. “The flesh,” refers to our sinful nature that still clings to Christians and with which we struggle on a daily basis. “The devil” refers to Satan and his horde of evil spirits who excite and entice us through the world and our senses. These things all afflict us and cause us to struggle with faith.
That is why Christians need to be constantly reminded of what Christ has done for us and what our response should be. The apostle Paul says, “Faith comes from hearing, and hearing through the word of Christ” (Romans 10:17). Our faith is built up as we have the gospel continually preached to us. Our churches need to be built on the solid preaching of the Word and the regular observance of the ordinances. Instead, too many churches spend their time, energy, and resources on the creation of “programs” that neither feed the sheep nor draw a clear distinction between godliness and ungodliness.
Consider the example of the Israelites in the Old Testament. God had performed great miracles in rescuing His chosen people from slavery in Egypt—the Ten Plagues, the pillar of smoke and fire, and the crossing of the Red Sea. God brings His people to the foot of Mount Sinai, gives them the Law and makes a covenant with them. No sooner does He do this than the people begin to grumble and lose faith. With Moses gone up on the mountain, the people convince Aaron, Moses’ brother, to construct an idol (against God’s clear prohibition) for them to worship (Exodus 32:1–6). They were no longer walking by faith, but by sight. Despite all the clear miracles God did in their redemption, they lost faith and began to go on their perception.
That is why God instructed the new generation of Israelites before going into the Promised Land to continually remind themselves of what God had done for them: “And these words that I command you today shall be in your heart. You shall teach them diligently to your children, and shall talk of them when you sit in your house, and when you walk by the way, and when you lie down, and when you rise” (Deuteronomy 6:6–7). God knows that the spirit is willing, but the flesh is weak (Mark 14:38), and so He commands His people to be in constant remembrance of these things.
In conclusion, we need to heed the example of the disciple Thomas. When Thomas heard the stories of the resurrection, he wouldn’t believe them until he saw Jesus with his own two eyes. Jesus accommodated Thomas’ lack of faith by making an appearance to him and allowing him to see and touch Him. Thomas responds in worship, and Jesus says to him, “Have you believed because you have seen me? Blessed are those who have not seen and yet have believed.” Many skeptics today echo Thomas’ sentiment: “Unless I see Jesus face to face, I will not believe!” We must not behave as the unbelievers do. We need to continually keep in mind Paul’s exhortation to walk by faith rather than sight. We learn in the book of Hebrews that without faith it is impossible to please God (Hebrews 11:6) because faith is believing the Word of God and acting upon it, not responding to our perceptions.