Question: "How should Christians respond to someone who leaves the faith?"
Answer: Our understanding of anyone’s situation is limited, of course, but when a “Christian” leaves the faith or renounces belief in God, we do have some general guidelines for how to respond. In many cases of high-profile individuals leaving the faith, we observe that their departures from the faith were not “de-conversions” as much as “realizations.”
As individuals who leave their faith behind tell their stories, we often see that they gradually grew uncomfortable with and eventually rejected aspects of Christian culture. They knew for quite a while that they were going through the motions and simply “playing along” with Christianity. After a while, these individuals accepted that they lacked a deep or connected sense of truth. They didn’t change their ideology, per se, only their identification.
For most of those who turn their backs on God, losing faith really means recognizing they never had faith to begin with. What they had was a vague intellectual agreement with some of the tenets of the gospel, some family traditions, some social connections, and (in the high-profile cases) a bright career path. But, when questions arose, they didn’t have actual faith or trust in the Savior. By and large, that’s the reason people who once identified as Christians change their minds. It’s not that they were true believers, then stopped; it’s that they came to embrace the fact that they were never true believers at all.
Jesus’ parable of the four soils illustrates what happens in the hearts of those who fall away from the faith (Matthew 13:1–23). The seed springs up in the stony ground, and for a while things look good, but there was never any root. Lacking true depth, plants wither and die; lacking a true change of heart, so-called faith disappears.
But there is another legitimate possibility to explain the behavior of those who leave the faith—in another of Jesus’ parables. It could be that those who seem to fall away are undergoing a prodigal-type experience (see Luke 15:11–32). If they are truly saved, then what we see as their departure from the faith is a tragic victory of sin in their lives. Such willfulness will be resolved, eventually. Legitimate Christians can sin, and they can struggle with doubt, but they will come out of it, often after a time of divine discipline (see Galatians 6:1–5 and Hebrews 12:4–13).
Either way—whether those who leave the faith are like the stony ground or like the prodigal son—the situations are heartbreaking. Such instances should be addressed with love and honesty. It’s almost impossible for us to know, for certain, what’s happening in anyone’s heart (1 Samuel 16:7). But Scripture is clear that those who are born again cannot lose that status (John 10:28). It is also clear that even those who are saved can risk serious consequences for disobedience (see 1 Corinthians 5:5 and Galatians 6:7).
The best thing to do when we have doubts is recognize that God allows us the space to express them (Mark 9:24; Habakkuk 1:2–4). He knows we will struggle with our experiences (John 16:32–33). It’s critical to know that He provides answers when we seek them (Matthew 7:7–8). Scripture (John 20:31; 2 Peter 1:16; Luke 1:1–4) and nature (Romans 1:18–20; Psalm 19:1) both serve to provide evidence and reasons to believe. That does not make the answers simple, but they are there (1 John 4:1). We can and should seek the advice of those with more experience and wisdom to help us answer those questions (Proverbs 11:14; Philippians 3:14–15). Perhaps more than anything, it’s essential to remember that “I don’t understand” is not the same as “this cannot be true.” Most people who “de-convert” reach a crisis point where they do not agree with God and refuse to accept that they could be wrong; on the basis of that, they decide God does not exist. Sooner or later, what a person wants to believe becomes more important than any evidence to the contrary (see John 5:39–40).
Some questions are hard, and not all have happy answers. But there are answers. Many seekers and skeptics have found them (1 Peter 3:15). Our prayer is that those who leave the faith will come back to the truth. If they don’t, it only proves that merely saying, “I am a Christian,” is not self-authenticating, even when a person is sincere (Matthew 7:21–23; Mark 13:13).