Here in the West we’ve had religious freedom for many centuries. Classical western liberalism has formulated a doctrine of religious freedom that’s been accepted by both Christians and non-Christians (at least up until recently!). Indeed, Article 18 of the UN’s International Convention on Civil and Political Rights upholds religious freedom as a fundamental human right.
But according to American author and theologian Jonathan Leeman, this modern understanding of ‘religious freedom’ is problematic. In his book, ‘Political Church – The Local Assembly as Embassy of Christ’s Rule’, Leeman argues that the secular definition of religious freedom has within it the seeds of its own destruction. That is, modern ‘religious freedom’ may well undermine Christian religious freedom.
It sounds ominous, especially as we grapple with religious freedom here in Australia. But Aussie Christians would do well to understand his concerns:
1) Modern Notions of Freedom of Religion Depend on ‘Freedom of Conscience’
But ‘Freedom of Conscience’ assumes a neutral moral viewpoint (that doesn’t exist).
Modern formulations of religious freedom are tied closely together with ‘freedom of conscience’ – the freedom to live according to one’s moral point of view (see for example Article 18 of the ICCPR).
‘Freedom of conscience’ has been a useful term throughout modern history, as both religious and non-religious agree that everyone has a conscience, and this conscience should be protected (as far as possible).
But this view of freedom of conscience assumes moral neutrality. It depends on ‘a view from nowhere. [Freedom of conscience is used] for the sake of public accessibility and in order to claim impartiality between competing religious demands.’ 
In other words, by appealing to the so-called ‘neutral’ view of freedom of conscience, we can adjudicate between competing demands for freedom (e.g. between the proverbial Christian wedding cake baker and the gay couple).
But here’s the problem:
The trouble is, if there really is no such thing as a view from nowhere [i.e. moral neutrality], and if the liberal doctrine of religious freedom continues to pretend standing there, “religious freedom” is not necessarily free. It is a way of cloaking the gods of the moment in the pretend garb of neutrality. 
Underneath terms like ‘freedom of conscience’ is an ideology, a worldview (or ‘gods’, as Leeman puts it). This ideology may be hidden, but it’s not silent: it determines the meaning of ‘freedom of conscience’, and therefore affects religious freedom.
Thus far, such ideology has been accommodating to Christianity, as it’s been heavily influenced by the Judeo-Christian worldview. But the underlying ideology is shifting, and Christianity is coming under increasing pressure as a result.
2) In the Secular View of Religious Freedom, The ‘Conscience’ Is Given Final Authority.
And God is removed from the religious freedom discussion.
The underlying ideology driving modern notions of religious freedom is not Christianity, according to Leeman:
Appealing to the inviolability of the conscience as this publicly accessible stand-in for religion has the ironic effect of removing God from the doctrine of religious freedom, which is why…it stands on a view from nowhere. In public terms, it invests the conscience with final authority.
After all, the doctrine must be something both believers and unbelievers can agree to. The two groups cannot agree to God’s existence, but they can agree upon their desire for a free conscience. As such, God is removed from the religious-freedom contract, objectively speaking, in spite of whatever pious subjective motivations the believer may quietly harbour. 
This shouldn’t surprise us. After all, we don’t hear lawmakers invoking God when talking about religious freedom: the free conscience is what concerns them, not what the Bible says.
But removing God from discussions of religious freedom opens up Pandora’s box:
3) Who Determines The Limits of Religious Freedom?
Without God, ‘religious freedom’ becomes open to abuse.
What happens if we remove God from the picture of religious freedom? The limits of religious freedom come up for grabs, and other ideologies start dictating them:
The doctrine of religious freedom becomes unaccountable to any standard of right, divine or otherwise. What’s to ensure that its philosophical services will be hired only by upstanding and virtuous monotheistic religions? What’s to prevent other parties and interests from employing it for ends besides the worship of God?
Defenders quickly assert that, of course, no one advocates religious freedom or conscience “without limits.” But this misses the point. Where will those limits come from? Establishing limits requires some worldview or religion to draw them, which means that someone’s religion must work covertly in the background. 
When freedom of religion was originally devised in the West, the underlying worldview was some form of Christian theism.
But what happens when Judeo-Christian limits to religious freedom are no longer in the background, informing religious freedom?
[R]eligious freedom” or the “free conscience” begins to protect all kinds of things that the original architects never intended and to prosecute the architects for some of their religion-driven practices.
For example, there used to be a consensus here in Australia that ‘religious freedom’ included the right of religious schools to operate on the basis of their religious teachings, even in the employment of staff. But such a consensus no longer exists: a Bill was introduced by Penny Wong last year that would have removed the right of religious schools to only hire staff who upheld their religious ethos.
In other words, religious freedom is starting to mean something other than what Christians would want it to mean.
4) Modern Religious Freedom is Reduced to a Battle Between The Religious Conscience vs. The Non-Religious Conscience
But why should a religious person’s conscience be more important?
If religious freedom is driven by secular conceptions of ‘freedom of conscience’, then it increasingly becomes a battle of consciences:
Christians argue against… court ordered demands to provide services to same-sex weddings, claiming that these requirements burden their conscience. But in so doing they merely pit one conscience’s burdens against another’s… And why should the believer’s conscience count for more?’ 
Where To From Here?
If the underlying ideology driving modern religious freedom is shifting away from Judeo-Christian assumptions, then religious freedom laws aren’t as likely to defend a Christian’s religious freedom.
Does this mean we give up on speaking for religious freedom?
Not at all. Not least, because we’re commanded to pray for it (1 Tim 2:1-4): it is a public good (when biblically defined).
But we need to beware of accepting non-Christian definitions and assumptions about religious freedom. Instead, we should clarify the underlying ideologies that drive terms like ‘religious freedom’. And as the opportunity arises, we should question these ideologies, and show why the Christian worldview makes for a better foundation to public policy, including for religious freedom.
 Jonathan Leeman, Political Church – The Local Assembly as Embassy of Christ’s Rule (Downers Grove, IL: IVP, 2016), 87.
 Leeman, Political Church, 87.
 Leeman, Political Church, 87-88. Emphasis added.
 Leeman, Political Church, 88.
 Leeman, Political Church, 89.