What is chaste love? Why should a Christian live a chaste life?
A chaste love is a love that defends itself against all the internal and external forces that might destroy it. That person is chaste who has consciously accepted his sexuality and integrated it well into his personality. Chastity and continence are not the same thing. Someone who has an active sex life in marriage must be chaste, too. A person acts chastely when his bodily activity is the expression of dependable, faithful love. Chastity must not be confused with prudishness. A person who lives chastely is not the plaything of his lusts but, rather, lives his sexuality deliberately, motivated by love, and as an expression of that love. Unchaste behaviour weakens love and obscures its meaning. The Catholic Church advocates a holisticecological approach to sexuality. This includes sexual pleasure, which is something good and beautiful; personal love; and fruitfulness, which means openness to having children. It is the understanding of the Catholic Church that these three aspects of sexuality belong together. Now if a man has one woman for sexual pleasure, a second to whom he writes love poetry, and a third with whom to have children, then he is exploiting all three and really loves none of them. (YOUCAT questions 403-404)
How can anyone live a chaste life? What can help?
Someone lives chastely when he is free to be loving and is not the slave of his drives and emotions. Anything, therefore, that helps one to become a more mature, freer, and more loving person and to form better relationships helps that person to love chastely, also. One becomes free to be loving through self-discipline, which one must acquire, practice, and maintain at every stage of life. It is helpful for me in this regard to obey God's commandments in all situations, to avoid temptations and any form of double life or hypocrisy, and to ask God for protection against temptations and to strengthen me in love. Being able to live out a pure and undivided love is ultimately a grace and a wonderful gift of God.
Does everybody have to be chaste, even married people?
Yes, every Christian should be loving and chaste, whether he is young or old, lives alone or is married. Not everyone is called to marriage, but everyone is called to love. We are destined to give our lives away; many do so in the form of marriage, others in the form of voluntary celibacy for the sake of the kingdom of heaven, others by living alone and yet being there for others. All human life finds its meaning in love. To be chaste means to love with an undivided heart. The unchaste person is torn and not free. Someone who loves authentically is free, strong, and good; he can devote himself in love. Thus Christ, who gave himself up completely for us and at the same time devoted himself completely to his Father in heaven, is a model of chastity, because he is the original model of strong love.
(From the Catholic Youth Catechism)