Members of the early Church often used the sign of a fish to identify themselves as Christians. Many of the early disciples - followers - were fishermen, and Jesus promised Peter that he would be a 'fisher of men'.
But there was another reason for choosing this sign. The word for 'fish' in Greek - the common language of the day - was 'ichthus', which (in Greek!) gives the initial letters of 'Jesus Christ, God's Son, Saviour' - which is as good a summary of the Christian faith as anyone has yet produced.
Christians believe that God was present in a unique way in the person of Jesus of Nazareth. His words and His actions are evidence of this, and you can read His words and read about His actions in the pages of the New Testament.
People sometimes talk about 'Jesus Christ' as if 'Christ' were His surname. But the word is actually a title or a description: it is the Greek word for the Hebrew 'messiah' and means 'anointed one' - someone special, someone with a special role, task and calling. Jesus did not decide to be different: He was chosen by God.
Christians believe that there is only one God, but that this one God is somehow three persons: Father, Son and Holy Spirit. We don't understand it, but then, it is not surprising that some aspects of God's nature are beyond our understanding. We choose to love, worship, follow and obey this God Who has revealed Himself in the person of Jesus the messiah - and, as we do this, we too become children of God.
Christians believe that things so often go wrong in peoples' lives because we make the wrong choices; and we make the wrong choices, in part, because we are all flawed, broken and damaged. We need to be saved not only from the mess we create, but also from the darkness within us. The good news is that, in Jesus, God offers not only to forgive us for what we have done wrong, but also to re-form us and to re-new us, to help us fully become the people He created us to be.
The only thing that Christians are required to do is to love.
Jesus summarised the Jewish law in this way: "Love God with everything you've got, and love your neighbour as yourself."
Christians have always met together. Since we are all children of God, we meet together as His family: to worship Him, to share and celebrate His life together, to seek to understand how we can best love each other and the people around us, and to pray for strength and guidance.
There are no religious practices that are shared by all Christians. Christians are united by love and by their union with Jesus, and not by any religious practice or ritual, but the following practices are often associated with the Christian faith.
Baptism is a ritual that involves immersing someone in water, or sprinkling them with water. Some Christians baptise babies, some only baptise people when they have chosen to follow Jesus, and some do not baptise at all.
Within some Christian traditions, the Christians who have distinguished themselves in some way are given the description of 'saint'. Other traditions remember and celebrate their special people but don't have any special title to give them, and other traditions recognise no special people at all, apart from Jesus.
Many Christians gather together on a Sunday, but some do it on a Saturday, and increasing numbers are choosing to meet during the week instead. Many traditions choose to celebrate numerous feasts and festivals, but other traditions have no special days, and some have just one or two each year. Easter Sunday, the celebration of Jesus' resurrection, is the closest thing Christians have to a common celebration - and even then, when it is celebrated, it is celebrated on different days in different traditions.