What age of child? Are you attempting to tackle the whole process of development in this over-simplistic question?
Children develop and at certain stages can start to appreciate critical thinking, etc. but not in the early stages. They need something stable and that is usually provided in a simplified version of a parent's preferences.
To throw in a weak analogy, kids in a multi-lingual home will learn to speak several languages, which helps develop their thinking, however they usually settle on one particular language in certain given circumstances (such as speaking to a parent who only has one of the languiages). That doesn't counfound their development of other languages but it does give some clarity when it comes to communicating. All they really want in their young years is to be understood and to understand. They really don't care whether one language is better than another as it is simply a tool.
We all "think" using certain frameworks, constructs and metaphors. They are useful because we hold them in common. If we want to learn critical thinking ability then we need to have mastered a starting point of one framework before being able to properly examine and contrast it with another. It is simply a tool.
In most school systems the ability to learn is built gradually and those who move on to Bachelors-level study are taught the ability to research information for themselves; at Masters-level study they are taught to critically analyse what they research; and so on. This is a natural process that meets the needs of a developing mind. You'll note that the higher level of studies are engaged by young adults, though they can be tackled by more advanced adolescents.
The point I'm attempting to make is that its all well and good applying our adult standards to what we think could be helpful to a child but it doesn't take into account the abilities and capacities of young minds. They need stability and simply tools with which to inter-relate with the world around them. For that reason I would suggest that if a child is raised with a particular belief-set (religious or otherwise) it is likely to be advantageous rather than detrimental.
A final example: the abundance of proverbs, rhymes and stories that and interwoven into the fabric of our cultural heritage enables us to communicate more quickly. We have built upon the shoulders of those who went before and are thus able to shortcut a long dialog and get to the heart of what we're attempting to communicate by usiong these common themes with a few choice words of explanation to focus our point. In the West we have been steeped in Biblical and Shakespearean stories, even when folks don't know the source of these sayings.
For example:
There was a child born in an outhouse whose family ran from oppressors to another land then up to a backwater village in their own. As the child grew he learned lots of things and was a likeable chap. When he became an adult he started teaching people to think critically which resulted in hatred from the uni-dimensional society leaders around him. Eventually they had him assasinated but his martyrdom resulted in a movement that would eventually inflame the world beyond the borders of his own land. Some rallied to the banner to gain power over others, but the underlying precepts of: outgrowing the selfishness of putting first your self, tribe, country and even world; embracing others who differ from us; and thinking critically about why we act the way we act; would eventually cause such a regime to crack. An underdog became something more and so can we.
Its a powerful meme and a tool that carries a rich tapestry of meaning to those who have been raised with a similar story. Each of us will draw out the facets that particulary appeal to us and our current stage of development. Its a story that can be revisited at many different points in our lives and inspire us to greater things. Would you rather learn of some such story (or another like it) as a child or a pensioner?
