There are several dangers to biblical Christianity that have come about through progressive ideology. Progressive ideology essentially stems from non-biblical positions about the nature of truth (that it is relative), the nature of people (that people are basically good) and the nature of scripture (that it should change with the times.) It's rooted in enlightenment thinking, modernism, and post-modernist thinking especially, which has surged across Europe and the United States in the last 30 years. Progressive ideology stems from the culture and politics of western civilization, slipping into the churches across the west and affecting the core teachings of many important movements.
The direct dangers are in the lowering of the truth of scripture into the realm of philosophical relativism (there is no truth) and the general ideology of progressivism (a series of political and social causes guided by a regressive utopianism that seeks to constantly reinvent society.) They tend to change how we view scripture; Instead of every word of the Bible being the inspired word of God that we regard as the authority over us, the progressive stands over the scripture and thinks of the scriptures as stories, that may or may not be factually true, and interprets and re-interprets the scriptures to fit with their own beliefs and ideas about how the world is. So instead of the Bible guiding us and being the authority over us, the roles are swapped and the person is guide and judge over the Bible, changing and reshaping the Bible as they see fit, generally to make it fit in with modern cultural views on issues like marriage, abortion, gender, sexual practice, and general philosophy of life.
Essentially the Bible can be reinterpreted to mean anything, on any issue, in the progressive worldview. Of course not all under this ideological umbrella are the same, some will have a slightly higher view of scripture or a lower view of scripture. But we're speaking in general terms.
That is what we need to stand against in the west today, because once the Bible is lowered and removed from a position of authority in our lives, anything goes. Everything suddenly becomes up for revision, creation, moral teachings, life and liberty, even the atonement and resurrection of Jesus Christ. Everything goes on the chopping block, maybe not all at once, but the door is opened to that possibility.
Progressive ideology tends to affect many areas of the churches of the United States and Europe. The teachings of Freud, Marx, Hagel, Kant, and other atheist thinkers tend to be the roots from which progressive ideology grows and spreads. In the United States, people like Woodrow Wilson, Herbert Croly, FDR, and Saul Alinsky have pushed forward progressive ideology on the political front.
Progressives tend to support politically: Bigger government, large administrative bureaucracies, democratic socialism, redistribution of wealth, unlimited welfare, abortion on demand paid for by others, free healthcare, free college, and unlimited unbridled immigration irrespective of national laws.
The fact that churches have been affected by progressive ideology is simply a logical consequence due to the affect that western civilization itself has been thoroughly transformed and reshaped by progressive political and cultural ideology. That is the simple fact. Far from starting off in the church, it's simply a growth from culture into the church.
Key issues today that progressives advocate for are things like switching the church's position on gay marriage to support and affirm gay marriage. This would mean pastors would marry gay couples, gay/lesbian/transgender individuals could become pastors, and pastors would probably be required to ignore the scriptures in the Bible that forbid homosexual practice. Another key issue would be legalizing and supporting abortion. Imagine church abortion clinics, or churches arm in arm with Planned Parenthood, helping to abort unborn children by the tens of thousands. There are dozens of other issues pertinent, climate change, gun control, redistribution of wealth, increased taxation, and swiping for church's tax exempt status. Perhaps one of the most disturbing trends are the persistent attacks on religious liberty by progressives in the political sphere. Ironically progressives attack conservative Christians for advocating for religious liberty, a right which they exercise on a daily basis, which is currently on the chopping block, at the altar of political correctness, gender ideology, and LGBT ideology.
The dangers are great from the progressive ideology, but very often the issue seems to take care of itself. Progressive churches collapse in on themselves, and people stop attending, because people are looking for the truth, not a truth, not a relative opinion, or a viewpoint or a universalist one of many ways to the summit, but people are looking for solid truth, a rock to stand on, and progressivism offers a wishy-washy "love above all else" which jettisons truth, ethics, and revelation for the sake of not offending anyone.
Love is indeed a key, core value of the biblical Christian worldview. But biblical Christianity is more than simply "love is love" in isolation, it's a spectrum of core ethical concepts including grace, mercy, judgment, obedience, moral precepts, faith, sacrifice, self-denial, and biblical love. So when love is elevated above truth, above grace, above obedience, above the Bible, and even above Jesus Christ himself, it becomes an idol, a false teaching, a worldly love, that is in fact, not love at all.
So what is biblical love? Biblical loves involves a great deal of truth. While worldly love would insist on accepting any behavior, endorsing any practice that pleases the culture, and never offending anyone no matter what, biblical love is deeper than that. Biblical love is that Jesus Christ was slaughtered for our transgressions on the cross.
Biblical love is that Jesus spoke truth to power, and yet gave grace to the weakest. Biblical love is warning someone when they are in danger of hell. As biblical Christians we must be proponents of biblical love, which is in the context of grace and truth. Sometimes love is hard. Sometimes love means speaking a difficult truth.
Sometimes love means telling someone something they don't necessarily want to hear. The trouble with progressive Christianity is that they take worldly love, set it above all else, and use it as a bludgeon to attack the truth statements of scripture. This is not love, but something else.
In conclusion, to me it seems obvious that the word of God is objective, timeless, and inspired entirely of God, and has been preserved by God, as our guide book to knowing the living Jesus Christ, and understanding how Jesus wants us to live. This means even the most difficult scriptures that we struggle with are also the word of God.
There are many scriptures that I don't like, that I struggle with and wrestle with God to understand what they mean, but I keep holding out that fundamental trust that the Bible is in fact right, and if I don't understand something, maybe it's me who is wrong, not God's word. That's a faith we have to hold up, and it's reasonable, because as finite limited humans we can't see every angle. We don't see the whole picture, there will be things we don't understand. And that's OK. Because we're not God. And essentially what the progressive does, is the sin from all the way back in the garden, they reject God's authority, and play god for themselves, reshaping and changing what is right and what is wrong to suit themselves.
Let us never make that mistake. It was the mistake that ruined the garden, and sent Adam and Eve into the wilderness. They rejected God, embraced a sweet tantalizing lie handed to them by Satan, and as a result all of reality became fallen, and paradise was lost. So let us humble ourselves, hazard all on God's word, the Bible, and trust it above ourselves and our own limited judgments.