Who is my brother in Christ?

According to statistics roughly 33 percent of the world’s and 2.3 percent of India’s population is Christian. Would this be the answer to the above question? If we ask members of different denominational Christian churches the majority of them would not agree with such a simple statistical answer. They would say instead:

A Christian brother is someone …
… who has been baptised in a Christian church.
… who goes to a church every Sunday.
… who believes in Trinity.
… who confesses Jesus as Christ having appeared as man.
… who believes in Jesus’ death and resurrection.
… who speaks in tongues.
… who has accepted Jesus Christ as his personal Saviour.

Of course, we could continue this list with further common answers, which are often combinations of some or all of the above criteria. Who is right? How can I decide who my brother is, with whom I can have true, spiritual fellowship, with whom I can pray and praise God together and with whom I can share my life, joy, and sorrow—in the trust that we are one in Christ, connected by the Holy Spirit?

God has revealed the answer in the Bible so that anyone who decided to follow Jesus and therefore has a sincere longing for brotherly fellowship with other children of God can find out who his brothers are and who are not.

Why is this question important?

The seriousness of this question was pointed out also by Jesus when he warned his disciples of false prophets who come in his name but actually have nothing to do with him:

Watch out for false prophets. They come to you in sheep’s clothing, but inwardly they are ferocious wolves. By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles? Likewise, every good tree bears good fruit, but a bad tree bears bad fruit. A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit. Every tree that does not bear good fruit is cut down and thrown into the fire. Thus, by their fruit you will recognize them. Not everyone who says to me, “Lord, Lord,” will enter the kingdom of heaven, but only those who do the will of my Father who is in heaven. Many will say to me on that day, “Lord, Lord, did we not prophesy in your name and in your name drive out demons and in your name perform many miracles?” Then I will tell them plainly, “I never knew you. Away from me, you evildoers!” (Matthew 7:15–23)

We have to be aware that there are people (many people!—verse 22) who claim to be Christians who might do even great and apparently good things in Jesus’ name but Jesus will regard them as evildoers at the last judgment. We as Jesus’ disciples are responsible to warn them and call them to a true Christian life. If they do not want to change we have to separate from them since a Christian cannot/must not have fellowship with evildoers. Instead, God wants to present us real brothers and sisters with whom we can be one body and light for the world.

How can we discern who a brother is?

Jesus says that the distinguishing criterion is their fruit (verse 20) and later he makes it even clearer: only those who do the will of his Father belong to him (verse 21).

These warnings of Jesus show that we cannot be superficial in our discernment of people who claim to be Christians. We really have to take time and make effort to get to know people’s lives, attitudes, way of thinking and the teachings they follow in order to see if they really do the will of the Father in heaven or just claim that Jesus is their Lord. In our “tolerant” world this examining approach might appear somewhat distrustful and might hurt someone but actually it should be a sign of longing for sincere relationships and deep unity. A brother or an open seeker will be willing to test and to be tested.

What are the fruits Jesus speaks about and what does it mean to do the will of the father?

→ Obedience to the word of God

First of all we have to realize that we cannot reduce it to accepting, confessing, and practicing some selected teachings of the New Testament even if they are true in themselves. The entire Bible is the revelation of God so if someone loves God he loves every word that comes from His mouth and wants to obey it regarding practical life as well as doctrinal questions. This attitude is the most important sign of a Christian. Everything else follows from it.

Jesus replied, “If anyone loves me, he will obey my teaching. My Father will love him, and we will come to him and make our home with him. He who does not love me will not obey my teaching. These words you hear are not my own; they belong to the Father who sent me.” (John 14:23–24)

The word of God is compared to a double-edged sword:

For the word of God is living and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart. (Hebrews 4:12)

The confrontation with God’s word is often painful because it sheds light on things in our lives which we have to change or completely give up. A Christian is ready to undergo this confrontation and purification through the Word and does not want to justify his wrongdoings by ignoring or distorting the Word of God.

→ Readiness to give up everything for Jesus

I tell you the truth, unless a kernel of wheat falls to the ground and dies, it remains only a single seed. But if it dies, it produces many seeds. The man who loves his life will lose it, while the man who hates his life in this world will keep it for eternal life. Whoever serves me must follow me; and where I am, my servant also will be. My Father will honor the one who serves me. (John 12:24–26)

The readiness to die for ourselves and follow Jesus in everything is the prerequisite of bearing fruit. A Christian is not satisfied with having changed some things in his life but wants to leave everything that hinders him to follow Jesus.

Large crowds were traveling with Jesus, and turning to them he said: “If anyone comes to me and does not hate his father and mother, his wife and children, his brothers and sisters—yes, even his own life—he cannot be my disciple. And anyone who does not carry his cross and follow me cannot be my disciple.” (Luke 14:26–27)

→ Brotherly love

Losing one’s life means to lay it down for others as Jesus did:

My command is this: Love each other as I have loved you. Greater love has no one than this, that he lay down his life for his friends. (John 15:12–13)

A Christian has longing for brotherly fellowship and wants to share his life with other Christians. This is how we know who the children of God are and who the children of the devil are: Anyone who does not do what is right is not a child of God; nor is anyone who does not love his brother. This is the message you heard from the beginning: We should love one another. (1 John 3:10–11)

→ Concern for the right doctrines

As mentioned above being obedient to the word of God also means to be very serious about the right doctrines. If someone clings to doctrines which are not in accordance with God’s word or has a superficial, careless attitude regarding the right teaching he does not respect the word of God and is not a disciple of Jesus. Jesus was ready to die to reveal the entire truth to us. We see that he fought very much for it and did not agree to anything wrong for the sake of (superficial) peace with his fellow Jews. John also testifies the serious consequences of having false doctrines:

Anyone who runs ahead and does not continue in the teaching of Christ does not have God … (2 John 9a)

A Christian will separate from false teachings and people who want to cling to them.


It is impossible to make a full list about the criteria of being a Christian on a few pages. The above thoughts are just some helping guidelines which we have to keep in mind if we want to discern whom we can call our brother in Christ. John puts it in very simple words which comprise everything:

We know that we have come to know him if we obey his commands. The man who says, “I know him,” but does not do what he commands is a liar, and the truth is not in him. But if anyone obeys his word, God’s love is truly made complete in him.


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