How do you know that you are a Christian? This is a good and healthy question that you may have never asked, that you have been asking, or that you have recently asked. I assume that some within the hearing of this sermon have asked this question because this sermon series has caused you to ask it. Some of you may now be confused or even may be questioning as to whether or not you are a Christian. So, before we move on to the rest of the Sermon on the Mount, I want to use our time today to help you answer the question: “How do I know that I am a Christian?”
Permit me to begin by first clearly stating what I believe from the Bible concerning how a person is saved from the wrath of a holy God and forgiven by that same God for the sins that every person is guilty of. So here it is: “Salvation is a gift from God whereby a person is saved by grace alone through faith alone in Christ alone.” Nothing more and nothing less. So, what is the definition of faith according to the Bible? According to Hebrews 11:1, “Faith is the assurance of things hoped for, the conviction of things not seen.” The word for “faith” (pistis) can also be translated as “trust.” The type of faith a person must have in Jesus for the salvation of their soul is a trust and confidence that he is exactly what you need for the forgiveness of your sins and the salvation of our soul.
There is nothing that you can do to add to your salvation, take away from your salvation, or contribute to your salvation. This is the testimony of the Bible and the point of the first two chapters in the Ephesians, which is best summed up in 2:8-9, “For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast.”
Secondly, the salvation of my soul is not grounded on my works as a Christian but on the exclusive work of Jesus Christ. This is why I am convinced that once a person is truly saved, that person cannot lose his/her salvation. There are scores of Bible verses for why I believe this, but I will share with you something Jesus said: “My sheep hear my voice and I know them, and they follow me. I give them eternal life, and they will never perish, and no one will snatch them out of my hand. My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand” (John 10:27-30).
Shortly after I became a Christian, I attended a church on Sunday mornings and a youth group at an entirely different church on Friday evenings (the denominations I will leave unmentioned) that had such a positive and profound impact upon my life and soul. I would not be the man and pastor that I am today had it not been for those two very different churches. However, a part of the core of each of those church’s theological convictions was the common belief that a Christian was not eternally secure in their salvation and that a genuine Christian could possibly lose his/her salvation due to some level of grievous and unrepentant sin. Not long after I became a Christian, I read Ephesians and soon after that I read Romans; it was my time in Ephesians 1 and Romans 8 that I believe God used to convince me that the person who genuinely and truly is born again (John 3:1-21) will not indefinitely walk away from their faith or remain indifferent to their sin. I can say this with confidence in part because of what the apostle John wrote to a group of Christians in the epistle titled 1 John. We are told why he wrote his letter in 1 John 5:13, which states: “I write these things to you who believe in the name of the Son of God, that you may know that you have eternal life.” In his letter, John answered why some deconstruct their faith till there is nothing left, leave the faith altogether, or live as though they never really believed in the first place: “They went out from us, but they were not of us; for if they had been of us, they would have continued with us. But they went out, that it might become plain that they all are not of us” (1 John 2:19).
To be born again is to go from spiritual death with nothing good in my soul to offer to God to spiritual life and a new nature where I am now able to love, obey God, and to do good works that please God (see Eph. 2:10). Because I am born again, I am able to love and obey God on a level that was impossible for me to do so before I placed my faith and trust in Jesus for the salvation of my soul and the forgiveness of my sins. Now it is Jesus who keeps me secure in him and will never let me go.
Finally, based on what I read in my Bible, I believe the reason Jesus said that he keeps all who belong to him in John 10:27-30 is due to the simple fact that if my salvation was dependent upon my ability to keep myself secure in Jesus, I would lose my salvation a thousand times over. Every born-again Christian is what the Bible describes as “…a new creation” (2 Cor. 5:17). Listen to me. God’s terms regarding your salvation does not include you meeting him in the middle to do your part, and so long as you do your part, he will keep his end of the bargain. God’s terms regarding your salvation are that he meets you all the way because you were spiritually dead and the only hope you could even flinch in his direction was that you first experience a resurrection.
The evidence that this has happened to you is seen in the evidence of a resurrected life that is being renewed and changed day by day. Oh, my dear brothers and sisters, this is why the apostle Paul could confidently proclaim in 2 Corinthians 4:16, “So we do not lose heart. Though our outer self is wasting away, our inner self is being renewed day by day.” This is also why we can have confidence that what the apostle wrote to the Philippians is true for those of us who have been born again: “And I am sure of this, that he who began a good work in you will bring it to completion at the day of Jesus Christ” (Phil. 1:6).
In light of all that I have said, I will now walk you through what I understand the beatitudes teach us concerning what it means to be a Christian and how it is that you can know that you are indeed a Christian.
1. The Christian is a person who understands that the salvation of their soul and the forgiveness of their sin is possible only through Jesus.
To be “poor in spirit” is to recognize that there is salvation found in no one else except through Jesus Christ (Acts 4:12). It is not just the recognition of this truth, but the response to it. The Christian is the person who understands and believes that the only solution to his/her sin problem is the Son of God who was sent out of the love of God to live the perfect life we could not live for the purpose of dying in our place on a cross that we deserved for the purpose of experiencing the wrath of God that should have been ours to experience. The Christian is a person who arrived at the offer of God’s forgiveness with the awareness and understanding that it was nothing but the perfect mercy and grace of God that made such forgiveness available. There is no Christian who did not arrive at the cross of Christ as one who is “poor in spirit.”
2. The Christian is the person whose sorrow over his/her sin has led him/her to Jesus as the only way to be forgiven of all sin and reconciled to the God he/she sinned against.
The person who “mourns” is the person who grieves over their own sin and the sins of the world. The Christian is the person who was so grieved over their sin, that their grief led to a desire to want to turn from it to the only way to be forgiven of it. The only remedy to be comforted from the guilt we experience from sin is through the person and work of Jesus. It is the kind of mourning David experienced and wrote about in Psalm 51, “Have mercy on me, O God, according to your steadfast love; according to your abundant mercy blot out my transgressions. Wash me thoroughly from my iniquity, and cleanse me from my sin! For I know my transgressions, and my sin is ever before me. Against you, you only, have I sinned and done what is evil in your sight…”. (Psalm 51:1–4). The Christian is a person whose sorrow over sin led him/her to Jesus as the only remedy for sin.
3. The Christian is the person whose pride was overcome by his/her need for Jesus, a sorrow over his/her sin, and the recognition of the lordship of Jesus.
The “meek” person is a humble person. There is no person who is a Christian who did not first humble themselves before the cross of Christ. A person who truly understands their sin problem and mourns over that problem will have no problem humbling himself/herself before the only one that can fix their problem. All sin comes from a desire to be satisfied in anything other than the God who created us. The root of sin is the desire to be autonomous so that we can exercise lordship over our own lives. In order to come to Jesus, the savior, a person must come before him as their Lord in full surrender to his authority over their life.
Listen, you cannot receive Jesus the savior apart from Jesus the lord. This is something Jesus made impeccably clear throughout the gospels and what the New Testament writers make impeccably clear throughout the rest of the New Testament. At least 250 times the word Lord is used to describe Jesus. Jesus said of anyone who wishes to follow him: “Whoever loves father or mother more than me is not worthy of me, and whoever loves son or daughter more than me is not worthy of me. And whoever does not take his cross and follow me is not worthy of me. Whoever finds his life will lose it, and whoever loses his life for my sake will find it” (Matthew 10:37–39). As one pastor wrote of Jesus’ expectation of the Christian: “When Jesus called people to follow Him, He was not seeking companions to be His sidekicks or admirers whom He could entertain with miracles. He was calling people to yield completely and unreservedly to His lordship.”
4. The Christian is the person who hungers and thirsts after Jesus.
An understanding that Jesus is who you need, a sorrow over your sin that has led you to his cross, and a humility to die to your own will and live for his will, it creates in you a hunger and thirst for a righteousness that only Jesus can satisfy. This hunger is a desire to know Jesus in the same way the apostle Paul wanted to know Jesus: “I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord…. that I may know him and the power of his resurrection, and may share his sufferings, becoming like him in his death, that by any means possible I may attain the resurrection from the dead” (Phil. 3:8, 10). The word Paul used in these verses for “know” is the Greek word “ginōskō” which is an experiential knowing; it is a knowing that goes deeper than just cognitive reasoning; this is the kind of hungering and thirsting Jesus is referring to in his beatitudes. It is a hungering and thirsting that chases after Jesus because the Christian understands and is experiencing that Jesus is life.
To be a Christian is to be a person who believes everything Jesus claims to be and acts upon what he/she knows to be true:
- Jesus said, “I am the bread of life” (John 6:35-51), so the Christian hungers for him.
- Jesus said, “I am the light of the world” (John 8:12), so the Christian seeks after him.
- Jesus said, “I am the door of the sheep” (John 10:7-9), so the Christian finds safety in him.
- Jesus said, “I am the good shepherd” (John 10:11-14), so the Christian follows him.
- Jesus said, “I am the resurrection and the life” (John 11:25), so the Christian lives as though death is not the end of life.
- Jesus said, “I am the way, the truth, and the life” (John 14:6), so the Christian trusts him.
- Jesus said, “I am the true vine” (John 15:1-5), so the Christian abides in him.
Jesus is all he claimed to be and nothing less.
Lest you become discouraged because you are not yet where you think you need to be in your relationship with Christ, I do not think that to be a Christian you must hunger for Jesus, seek after Jesus, rest in the safety of Jesus, follow Jesus, live as though death does not bother you, trust Jesus, or abide in Jesus perfectly. As you grow in your relationship with Jesus, you will experience Jesus as the bread of life, the light of the world, the door of the sheep, the good shepherd, the resurrection and the life, the way the truth and the life, and the true vine in whom you abide more and more with each passing year. However, I do not think you can claim to be a Christian if you believe him to be less than who he claimed to be.
There is no room in your life for more than one Lord. This is why Jesus said, “Whoever loves father or mother more than me is not worthy of me, and whoever loves son or daughter more than me is not worthy of me. And whoever does not take his cross and follow me is not worthy of me. Whoever finds his life will lose it, and whoever loses his life for my sake will find it” (Matt. 10:37-39). The Christian is the person who discovers in Jesus a treasure more valuable than anything you already have or what this world can offer you (Matt. 13:44).
So how do I know that I am a Christian? You know you are a Christian because you really believe that he is the only remedy for your sins, the savior of your soul, the Lord of life, therefore you embrace him for all that he is. You may have prayed a prayer where you expressed your belief to God, you may have grown up in a home where you learned of Jesus and gradually moved into full faith in him. What saves you from your sins is the work Jesus accomplished on the cross for your sins, the validation of that work through his resurrection, and your mental, emotional, and intentional embrace of Jesus as your savior. The evidence that you truly believe in him is a love for him and all that he is (see 1 Cor. 16:22).
One pastor described biblical faith in Jesus this way: “To become a Christian—to be justified and finally saved—is to “embrace Christ.” Embrace! Not take between your fingers as one gets a boarding pass, shows it twice, and then, after the flight, throws it away.”
 For Bible verse on the eternal security of the Christian, see John 3:16-21; 6:37-40; Romans 5:1-11; 8:1-39; 2 Corinthians 5:16-21; Ephesians 1:3-14; 2:1-10; 1 Peter 1:3-9; 2:9-12.
 John MacArthur, The Gospel According to Jesus (Grand Rapids, MI: Zondervan; 2008), p. 25.
 John Piper, What is Saving Faith? (Wheaton, IL: Crossway; 2022), p. 63.