Pupils in Catholic schools must learn that the church's beliefs are "objectively true", and should not be taught about some major religions until they are 14 or 15.
The Catholic Church's lead body, the Bishops' Conference of Scotland, sets out this unequivocal advice for its schools in a document, This is Our Faith, aimed at P1-S3 pupils.
"We should not be mealy-mouthed, apologetic or deceitful about values being proclaimed in Catholic schools," Michael McGrath, director of the Scottish Catholic Education Service, told a recent conference on religious and moral education, at which he drew attention to the bishops' guidance.
The document is in draft form, pending Vatican approval. The bishops state they are exercising their "right and duty to determine the content of the religious education curriculum in Catholic schools".
Teachers should avoid "presenting all denominations or faiths as equally true", they declare, and add that "the aim in Catholic religious education classes will always be to form young people who follow Jesus". The guidance reads: "While respecting pupils' opinions and faith backgrounds, teachers must propose Roman Catholic beliefs and values as objectively true and eminently relevant."
The document in effect outlines a hierarchy of faiths to which youngsters in Catholic schools should only be gradually exposed. "The proportion of time allocated to learning about other world religions will be limited," it states.
The guidance continues: "Since the Church holds in particular regard the other so-called `Abrahamic' faiths, namely Islam and above all Judaism, pupils in Catholic primary schools will normally learn about these two other world religions from P3 onwards.
"This will not exclude reference to the beliefs of pupils from other faith traditions represented in the school, but indicates that such references should be exceptional (eg on the occasion of religious festivals)."
The document relegates other major religions, such as Hinduism, Sikhism and Buddhism, by suggesting RC pupils should not be exposed to them until S3.
There is still less room for atheism and humanism: "Inevitably, when using an anthropological approach to teaching by drawing upon the general experiences of the students, there will be some consideration of the non- religious symbols, rituals, important texts and beliefs that feature in society today.
"However, explicit phenomenological study of stances for living which may be independent of religious belief will not form part of the content of religious education in Catholic schools."
The document supplements national guidance (see right), which states: "Religious education, whether it be in denominational or non- denominational schools, enables children and young people to explore the world's major religions and views, including those which are independent of religious belief."
This is Our Faith throws light on crucial differences between RE outcomes and experiences in Catholic schools and those for religious and moral education in the non-denominational sector.
Although the latter emphasise Christianity's importance in Scottish history and contemporary life, learning about other faiths, traditions and viewpoints is deemed equally important.
By the end of P4, children in non-denominational schools should be equipped to say: "I am developing an awareness that some people have beliefs and values which are independent of religion." On leaving primary, they should have some understanding of how non-religious as well as religious beliefs affect actions.
By the end S3, pupils in nonCatholic schools are expected to apply "a range of moral viewpoints, including those which are independent of religion, to specific moral issues".
In dealing with "ultimate questions", such as "Is there a God?" or "What is life for?" Teachers in non-denominational schools are advised that "world religions may offer a variety of views on these topics" and such questions should be explored "from a standpoint that is inclusive".