I can not say, with absolute certainty that the best option for water baptism is the child or the adult, but I can safely say that we must respect the beliefs of everyone in this and in all other aspects of spiritual life. Christian faith is based on their beliefs and not "absolute truths." Certainly any Christian believes that Jesus is the Way, Truth and Life, for them, that is a truth with absolute value. But I do mean to relative doctrinal truths that claim to be "absolute truths."