This claim has come up in a number of places - this is only one example.
It's not actually true. I don't agree with everything in the attached PDF (which is not long, don't worry), but it is sufficient to give you the general idea.
The main stream culture, that which you see represented in news, TV, movies, etc. does not profess to be Christian, or extol values because they are Christian values. While many Christian values are accepted, they are accepted because they are already part of the culture. Christianity as such is portrayed as being backward, ignorant, and foolish.
Without Christian thought there is no reason why everyone should be treated equally. If you reject Christianity but accept the idea that everyone should be treated equally you have removed the underpinnings of that belief. The belief may persevere for some time but on careful examination it is not at all obvious that everyone should be treated equally (under the law).
Basically, everything in the modern Western world is Christian in its origins. Human rights, gay rights, transgender rights, capitalistic values, conservative sexual ethics, Black Lives Matter, modern science, environmentalism - all these have their roots in principles that were unknown before Christianity exploded onto the scene. Let's survey them:
I think this is a bit of an overstatement with use of the word “everything” but I mostly agree with the sentiment. Many of the principles around which the western world is built are principles of Christianity. This means that many of the societal norms and values are Christian in origin even if the people who hold those values are ignorant of that fact.
The world around us is built one judgment at a time as each person makes their decisions. That we live in a world where Christian principles are central speaks to decisions made in the past where the judgments were subject to the “examination” so to speak of Christian morality. In a culture where adherence to Biblical teachings was paramount there is a certain trust you can offer your fellow man where even if your judgments might be different you still both submit to the same higher authority. You disagree on the specifics but can genuinely trust that the goal of adhering as much as possible to Biblical teachings is shared. This is no longer the case. We may currently largely agree on some of the specifics because we are a part of the same culture but the view that we ought to adhere to Biblical teachings by virtue of the fact that they bear the authority of God is gone. As a consequence, the billions of judgments being evaluated daily are no longer subjected to the examination of Christian morality. I think it is sort of willful, optimistic blindness to suggest that a culture actively acting to suppress Christianity will nonetheless exhibit blossoming Christian principles. Watts alludes to this at the end of his essay “The incredible freedom and unimaginable agency offered by the gospel only brings life when we humans reflect the character of unique Yahweh, who created this entire cosmos. Since that character is most fully expressed in Jesus, the continued flourishing of modernity depends utterly on our imitating him. In such a case, never has Jesus been more relevant. This of course raises several more and searching questions: how well do we who own his name understand his gospel, and even more importantly, ourselves reflect his character?”
In summary, the “now” we are living in reflects past values so we observe the distinctly Christian fingerprint everywhere. The future our children will inhabit will reflect the principles we adhere to now. So taking a single snapshot and pointing at evidence of Christian values is slightly misleading.
Human rights are based on the principle that a human being has value simply by being human. This is not self-evident and nobody believed it in the ancient world. It is no coincidence that the idea of human rights arose in a Christianized West.
Agreed
Gay rights and transgender rights are based on the principle of freedom and equality for all, the end of oppression and discrimination. Freedom is a fundamentally Christian idea. It is Christian not to oppress people or discriminate against them. It is Christian to respect people's autonomy and ability to live according to their own moral values, not to force them to live according to your moral values.
In one sense I agree. We should not have different laws for gay or transgender people but my understanding is that we don’t. So it’s not clear to me what exactly we are talking about. I think often what is meant by “rights” is that all lifestyles should be equally facilitated and celebrated. This is not at all a Christian principle.
Regarding discrimination, we should clearly specify what we mean. The base meaning of the term is to tell the difference between things, which we obviously do all the time. The purpose of this is to act based upon a more finely grained approach to life. The type of discrimination Christianity teaches us to avoid is a mistaken discrimination, that is, taking a person’s race or status as though that is representative of the person themselves. This undermines proper discrimination as you are abandoning the fine grained approach and embracing the broad characterizations that could be significantly in error. Christians are called to be as shrewd as snakes, not to judge by appearances but with right judgment (i.e. accurate John 7:24). The current cultural mantra is that one should not judge at all but this is also not Christian. One should judge accurately. And I think it is accurate to say that homosexuality and transgenderism should not be praised and extolled but discouraged. Defining marriage to be between a man and a woman and insisting that men cannot become women is seen as an affront to lgbt which is in some sense true but to construe this as a removal of rights from people is inaccurate.
Capitalism is based on the principle of getting what you deserve as an individual, and of "thou shalt not steal." Both of these are Christian in origin, showing a wisdom embedded in the Old Testament that individuals punish and reward themselves by their own actions, and do not need external punishment and reward. Also the principle that each individual is accountable for his/her own actions, rather than the actions of his/her parents.
Agreed
Conservative sexual ethics are based on Christian values of monogamy and the idea that the purpose of sex is not pleasure but children and the strengthening of the marital bond.
I’m not sure I completely agree here, in that, I’m not so sure the Bible teaches that sex is not for pleasure. For sure, I have heard it claimed that Christians teach this but I haven’t actually heard a teaching like this. In any case, yes, the Bible certainly is the source of plenty of conservative sexual ethics.
BLM is based on the Christian principle that all human beings are equally valuable regardless of their race, and that discriminating against people based on their race is morally wrong.
I think it is actually based on the Marxist oppressor/oppressed narrative that has been adopted by critical theory. It gains significant traction because everyone else agrees that racial prejudice is unethical. But my impression is that actors within the BLM movement do not themselves refrain from racial prejudice, calling it out across the board, rather only when it fits the oppressor/oppressed narrative and only when it falls in the “correct” direction. BLM heavily relies upon division into and identification by group which goes against the principle of proper discrimination, dealing with people individually rather than as a member of a group. This is the classical definition of racism.
Modern science is based on the principle that there is intelligible order to the Universe. See Pope Benedict's beautiful response to this child in the section beginning "I am Giovanni, I am 17 years old."
Agreed
Environmentalism is based on the principle that the world is given to us to steward with wisdom and care, not to abuse as trash. See the current Pope's call for all people to care for the planet and not destroy it through greed.
I’m not sure I agree with this. I think one can make a case for environmentalism in this way but I’m not sure this was the impetus for the current environmental movement. In much of current environmentalism there is an underlying assumption that mankind is bad and any effect that mankind has on the world is bad. This is not at all a Christian principle.