I remember the tears I cried as I drove away from my Hindu grandfather's house in Malaysia – I knew this would be the last time I would see this frail but noble old man. I also remember getting an angry knot in my stomach when I thought about the doctrine of the uniqueness of Jesus, and the idea that not everyone will be saved.

The idea that it is through belief in Christ alone that someone can be made acceptable to God is a controversial doctrine to hold in a multicultural context, let alone in a multicultural family like mine. The exclusivity of what theologians call "salvation through Christ" sounds unfair, ungracious and unacceptable to a society that paradoxically finds the idea of an afterlife both a great comfort and a primitive or backward way of thinking. It is true that sometimes Christians have shown an ugly arrogance and a lack of compassion towards people considered unbelievers. But it is also true that the idea of an exclusive salvation is difficult for our culture to swallow. This doctrine feels like it might soon be under pressure in the Church, despite the fact that we still enjoy singing most of the lyrics to popular worship songs such as In Christ Alone and My hope is built on nothing less.

Does the Bible really teach that Jesus is the only way to God?

Here are the Bible verses that are most often used to support the belief that salvation is only available through Christ's life, death and resurrection:

"I am the way, the truth and the life. No one comes to the Father except through me" (John 14:6).

^"For there is one God and one mediator between God and human beings, Christ Jesus, himself human, who gave himself as a ransom for all people" (1 Timothy 2:5-6).

"All who have come before me are thieves and robbers, but the sheep have not listened to them. I am the gate; whoever enters through me will be saved" (John 10:8-9).

"Salvation is found in no one else, for there is no other name given under heaven by which we must be saved" (Acts 4:12).

These texts are pretty clear: "no other name" and "no one comes to the father" are pretty emphatic. But to be honest, proof texts alone are not a fantastic way of determining doctrine. We know how frustrating it can be to discuss theology with Jehovah's witnesses who use this model to argue what evangelicals perceive to be the opposite of the gospel. When forming our beliefs, we would do better if we tried to capture not just individual texts but the grand sweep of scripture. We would also do well to pay attention to historical creeds and confessions of the Church throughout the ages. Here are five reasons to believe that Christ is the only way to be saved:

1. The seriousness of sin

The Bible is very clear about the holiness of God. In the Old Testament this is apparent from the outset; the first sin in the garden of Eden leads to death entering the world as a punishment for human disobedience. The extensive and severe Old Testament laws tell us that God is morally pure and expects to be honoured in thought, word and deed. The sacrificial system is instituted to demonstrate the fact that sin is so serious that it leads to death. Yet we are told very clearly that:

"The law is only a shadow of the good things that are coming – not the realities themselves... It is impossible for the blood of bulls and goats to take away sins" (Hebrews 10:1-4).

Even the Old Testament sacrifices that God instituted for his chosen people are not sufficient to deal with the reality of human sin, so how much less will the systems of sacrifice that other religions offer? The writer to the Hebrews argues that "we have been made holy through the sacrifice of the body of Jesus Christ once for all" (Hebrews 10:10). Sin is therefore so serious that it cannot be dealt with through animal sacrifice; it can only be dealt with through the death of the Son of God. This helps us understand why Christ had to die as the "lamb of God who takes away the sin of the world" (John 1:29), and why Jesus is described as "our Passover lamb" who was sacrificed for us (1 Corinthians 5:6-8).

2. The death of Christ

There is a moment in the garden of Gethsemane where Jesus says "My Father, if it is possible, may this cup be taken from me. Yet not as I will, but as you will," (Matthew 27:39). The silence of God in Gethsemane and the events that transpire seem to offer the unspoken response that there was no other way that sin could be dealt with. The idea that Jesus was simply providing an alternative route to God for those that didn't like Judaism or any of the other ancient world religions seems to insult the nature of the relationship between God the Father and God the Son. If there was another way that human beings could be made acceptable to God, then would our heavenly father really have allowed his only Son to be offered as a sacrifice? To deny the exclusivity of salvation in Christ seems to render the cross meaningless at best, and cruel and unnecessary at worst.

3. Israel as God's chosen nation

The foundational story of Israel is God's choice of Abraham and Sarah to be the parents of a new nation. The purpose of their choosing was so that they would bless all the nations. These are two vital elements in the story of salvation. God is choosing a particular people in order to offer a universal invitation. This pattern helps us to understand how things work with Christ. Just as God chose – or dare we say elected – Abraham to be the means of blessing to all the nations, this is now fulfilled by the coming of Jesus. Christ is the ultimate outworking of God's promise to Abraham. To reject the idea of the exclusivity of salvation in Christ undermines the narrative sweep of the choosing of Abraham and the calling of Israel.

Perhaps understanding the exclusivity of salvation together with the doctrine of election may help us understand why this is not an 'unfair' doctrine. Yes, God is exclusive as to how people can be saved; there is only one way back to God as there is only one way sin can be dealt with. But, no; the fact that there is one way does not mean God is showing favouritism or elisitism, because God is universal in his offering of that salvation to all people through the good news of the gospel.

4. The reality of judgement and hell

Jesus, the most loving and holy person in human history, spoke about the reality of judgement and hell more frequently than anyone else in Scripture. In Christ's teaching, judgement, hell and punishment do not sound like some kind of theoretical possibility, but rather a certainty. The deciding factor of someone's final destination is continually referred to in reference to his or her response to Christ:

"They also will answer, 'Lord, when did we see you hungry or thirsty or a stranger or needing clothes or sick or in prison, and did not help you?' "He will reply, 'Truly I tell you, whatever you did not do for one of the least of these, you did not do for me'" (Matthew 25:44-45).

"Moreover, the Father judges no one, but has entrusted all judgment to the Son, that all may honour the Son just as they honour the Father. Whoever does not honour the Son does not honour the Father, who sent him" (John 5:22-23).

"Not everyone who says to me, 'Lord, Lord,' will enter the kingdom of heaven, but only he who does 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 perform many miracles?' Then I will tell them plainly, 'I never knew you. Away from me, you evildoers!'" (Matthew 7:22-23).

If Christ is not the only way to God then we need to reject Christ's teaching on hell and judgement too. As you may have noticed, in rejecting the doctrine of the exclusivity of Christ we end up rejecting large chunks of biblical teaching.

5. The missionary heart of the church

If all religions will ultimately bring people into a relationship with God then there seems little point in the missionary mandate. Why would the early Church have risked life and limb to get the good news of Jesus out to the world? Why would Peter, Stephen and Paul literally face death in order that the message of Jesus could get to Jews and Gentiles alike? Moreover, if all religions are different paths to the same God then it is incredibly arrogant to encourage anyone to be converted to Christianity. It would be like forcing someone to like your favorite football team or ice cream flavour. But, if Christ alone is the way to God, then it is immoral to withhold from anyone the opportunity to respond to him and his message. Hence Paul explains to the church leaders from Ephesus that he considers himself "innocent of the blood of all men" (Acts 20:16) because he has faithfully explained the gospel to every person he could.

Alternative Views

There are two views that affirm the uniqueness of the life, death and resurrection of Jesus and the exclusivity of salvation being possible only through Christ and yet still raise significant challenges to traditional views. The first is called "postmortem conversion" and the second is the idea that all people are ultimately saved by Christ's death on the cross.

Proponents of the former believe that during punishment in hell after death there is another opportunity for people to be converted. It is argued that this means that ultimately God's purposes win out as "God wants that none should perish" (2 Peter 3:9). This is a highly attractive view as it still allows for a passionate commitment to mission. It also has an interesting history. The early Church leader and theologian Origen, who lived between 184-254 AD, was the first significant proponent of this view, arguing that ultimately the horrors of hell were remedial and given long enough time there everyone will eventually turn to God and be saved. So Jesus is the means by which everyone is rescued. Jesus' death on the cross is not just an accident of history or a miscarriage of justice but really does accomplish something.

I empathise with the motivations behind this approach. Many of my friends and family profess either no religious faith or belief in another religion, and the idea of any of them experiencing eternal punishment is unbearable. But of course personal preference has never been a good source of truth – just ask oil executives about global warming or the landed gentry about a mansion tax. What the Bible actually teaches has to be the bottom line for any serious Christian approach to this or any subject, and two of Jesus' parables speak to this view. 'Lazarus and the rich man' in Luke 16 makes the explicit point that no one can cross from hell to heaven after death. We recognise that parables do not give a blue print picture of the nature of hell, but this detail does seem important to the central thrust if what Jesus is saying. Equally, there is a finality and eternal quality to the judgement described in the parable of 'The sheep and the goats' in Matthew 25:45-46: "'Truly I tell you, whatever you did not do for one of the least of these, you did not do for me.' Then they will go away to eternal punishment, but the righteous to eternal life."

The second alternative view is that all will be saved through Christ even though they did not know it was him who saved them. The terms 'anonymous Christians' or 'inclusivism' are often used to describe this approach. Some saw a homily on Mark's Gospel that Pope Francis gave in 2013 as a form of affirmation for this view:

"The Lord created us in His image and likeness, and we are the image of the Lord...The Lord has redeemed all of us, all of us, with the Blood of Christ: all of us, not just Catholics. Everyone! 'Father, the atheists?' Even the atheists. Everyone!".. We must meet one another doing good. 'But I don't believe, Father, I am an atheist!' But do good: we will meet one another there."

That is not necessarily where Pope Francis ends up, however. He could simply be arguing that Christ came to save everyone, not just Catholics, but that personal faith in Christ is still necessary.

I have sympathy with this inclusive approach to salvation. It affirms the importance of the cross of Christ and offers hope to those who have not come to faith. It has been popularised recently by Rob Bell in his book Love Wins, and it also sounds a little like the ending of CS Lewis' The Last Battle, which evangelicals have always found awkward as Lewis seems to affirm the faithful worship of another God, Tash:

"Therefore, if any man swear by Tash and keep his oath for the oath's sake, it is by me that he has truly sworn, though he know it not, and it is I who reward him. And if any man do a cruelty in my name, then, though he says the name Aslan, it is Tash whom he serves and by Tash his deed is accepted."

The trouble is that again it is hard to find biblical support for this. Both the New Testament and the  Old Testament are set within pluralistic contexts where other religions are regularly encountered and yet not a positive word is offered of any other religions. The Bible is very clear that everyone is made in the image of God and that even our enemies should be shown love and respect. But at the same time, Scripture is unrelenting in its denunciation of other gods as "idols". This is a recurring theme enshrined in the moral centre of the Old Testament: the 10 commandments. Indeed, idolatry is so serious that the first two commandments prohibit it. Only one command was seen as necessary to forbid murder but idolatry gets a double portion. Other religions are not seen as benign entities or alternative routes to God but as oppressive to the worshipper and insulting to God.

Does belief in the exclusivity of salvation through belief in Christ alone lead to arrogance?

There have definitely been examples of people claiming to be Christians who are imperialistic, xenophobic and racist. Westborough Baptist Church is an easy example of a church that shows little of the grace of God to those who do not believe when they picket funerals and burn Korans. But to infer from their example that holding to the same approach of salvation in Christ alone automatically leads to this kind of behaviour is unwarranted. Indeed it would be as unhelpful as assuming that every Muslim is an ISIS supporter. Believing that all human beings are intrinsically valuable persons independent of their gender, age, abilities, sexuality or beliefs is a fundamental assertion of any theology that dares to call itself Christian, and is underlined by Jesus' injunctions that believers must love their neighbour and even their enemy.

A Christian response to other religions must include a commitment to protect the right to freedom of religion for all faiths, and look for opportunities for co-operation when possible. But it must also recognise that loving someone does not mean you have to agree with them and it can mean being willing to have the hard conversations with them. Loving someone can mean warning them of danger and pleading with them to come to their senses. Loving someone will involve respectfully and graciously sharing the good news of Jesus with them, recognising that, as DT Niles famously said: "Christianity is one beggar telling another beggar where he found bread."

Dr Krish Kandiah is President of the London School of Theology. Follow him on Twitter @krishk.