Although Christians today and in the past are highly diverse, they share a long history of concern for and attention to children. They have prayed, studied, and worshipped with children in their homes and congregations. They have established many institutions to serve children, such as orphanages, schools, and pediatric hospitals. They have educated children and founded schools, colleges, and universities around the world. They have written religious education materials for use in the home, in congregations, and on the streets. They have composed songs and hymns and published sermons, stories, prayers, liturgies, and Bibles explicitly for children.

Christians have built many of their beliefs and practices regarding children on their understandings of the Bible. Although there are slight variations among major branches of Christianity regarding the biblical canon, the Bible for Christians generally includes the twenty-seven books of the New Testament and the same material found in the Jewish Tanakh, although Christians divide and re-arrange this material differently and call it the Old Testament. The books of the Bible are teeming with direct and indirect references to children and adult--child relationships. Biblical passages refer to the conception, birth, and lives of named and unnamed children. The Bible also portrays complex and diverse examples of adult--child relationships and responsibilities. Adults are commanded to teach, instruct, and train children “in the way” they should go (Proverbs 22:6) and bring them up “in the discipline and instruction of the Lord” (Ephesians 6:4). Children are commanded to “honor” and “obey” their parents (Ephesians 6:1–3). The New Testament gospels also include passages about Jesus’ own birth and childhood and many stories about Jesus healing, welcoming, and blessing children. Jesus also refers to adults as “children of God” and claims that “unless you change and become like children, you will never enter the kingdom of heaven” (Matthew 18:3; cf. Luke 18:17; Mark 10:15). Even biblical visions of hope and restoration are often described with the help of images of children. “The wolf shall live with the lamb,” and “a little child shall lead them” (Isaiah 11:6); and “the streets of the city shall be full of boys and girls playing in its streets” (Zechariah 8:5).

Every person on earth once was or is a child. It is a role all human beings share. Not all human beings are siblings or parents. Not all are aunts or uncles. We all have different types of roles and responsibilities, whether at home, at work, or in civic life, and we live in different familial, social, and political contexts. Clearly, our conceptions of childhood vary widely across time and traditions. We do not even agree when childhood ends and adulthood begins. Yet, however we might define childhood or interact with children, we acknowledge that all human beings begin life as infants and develop as children. Furthermore, infants and children make up a significant portion of many communities. Even if we do not agree on a set age for the end of childhood, we can appreciate the importance of children just by noting that around the world today approximately one-third of humanity is under the age of 18.

Since all human beings once were or are children, children and childhood are bound to be central themes in ethical and moral reflection. Indeed, over centuries and across communities and cultures today, human beings have raised a number of fundamental questions about children and our commitments to them. Who or what is a child? How or why do we value children? What do parents owe their children? What are society's obligations to them? What are a child's basic needs? How do we ensure those needs are met? Who is responsible for a child if a parent dies or in cases of divorce? Who should intervene if a parent or guardian appears to neglect or to exploit a child? Who can or should speak on behalf of a child? What are children's own obligations to parents and the wider community? What are their particular roles, capacities, duties, and responsibilities? When should a child take on adult responsibilities? When does childhood end and adulthood begin? Do children themselves have rights? Does the international community have responsibilities to children? How far do our obligations to children outside our families or local communities extend?