The average person in a functional democracy would advocate for secularism to some extent. The belief that there has to be a separation of the state and the church is seemingly uncontroversial. However, religious institutions continue to play a vital role in the political landscape of many states. Even the most secular states often conceptualise the rights and laws which govern their society according to some religious reasoning. Many politicians push for legislation which aligns with and is justified by religious thinking. Christianity remains the most prominent religion in the world, accounting for about 31% of the world's population,  so naturally, Christian beliefs have a significant effect on politics.
There are as many political attitudes within Christianity as Christian denominations. Many Christian groups use text from millennia ago to justify marginalising attitudes to women and minority groups such as the rainbow community, citing tradition. Religion can be manipulated to subjugate women despite women tending overall to be more religious. Former President Jimmy Carter echoed the sentiment about religious policy and women when he argued that "women are treated more equally in some countries that are atheistic or where governments are strictly separated from religion". The scriptures in the Bible have been used as the bases upon which conservative policies and laws are justified in many places around the world particularly leading to legislatures not passing certain laws or rescinding previously existing legislation. For example, the controversy around abortion and general female reproductive rights in the Bible Belt in the USA are a manifestation of the Christian belief that abortion is a sinful deed. Similarly, pro-LGBTQIA+ legislation has faced significant backlash in areas like Texas where the conservative group Texan Values has rallied against legislation which would facilitate the transitioning process for transgender individuals by making it easier to change their birth certificates.  Given the political incentive of electoral victory and the sheer number of individuals with conservative Christian values, Christian based groups such as Texan Values have a significant amount of political capital and sway. The introduction of religion in politics exacerbates inequality by promoting sexist, homophobic and otherwise illiberal politics.
Religion is largely interpretative, so the spate of illiberal policies in conservative areas are not inherent to Christian faith but rather to how individuals in specific contexts choose to enact their religious beliefs. Within various Christian denominations, there are some liberal institutions such as Methodist churches where the ordination of women, for example, is not a contentious issue. Micheal Gerson, a columnist for the Washington Post and a former advisor to President George W. Bush also makes the case for why religion is not a breeding grounds for discrimination and oppression. He points to the backlash that President Donald Trump's migrant child separation policies received from religious leaders, resulting in a partial backdown as evidence of the positive role religious institutions can play in politics. 
Individuals should have a significant amount of liberties regardless of sex, gender or sexual orientation and any other identities they may have.
[P1] Religion promotes illiberal values [P2] Individuals who subscribe to these illiberal values have significant political power
Rejecting the premises
Religion allows for interpretation and it not as prescriptive.