The influences of Judeo-Christianity (a term that represents the certain set of Abrahamic Middle-Eastern religions, namely, Judaism, Christianity, and Islam) perpetuated themselves across Europe over fifteen hundred years ago. The process of the western world's Christianization started with the creation of the canonical texts and the church hierarchy in Rome, and got into full swing in 312 C.E. when the Roman Emperor Constantine I made Christianity Rome's national religion. The religion spread like wildfire, and through the Great Schism, the Crusades, the rise of the Roman-Catholic Church, and later the Protestant reformations, Christianity took permanent hold in Europe along with (pre-existing) Judaism. The Renaissance and the industrial revolution saw the rise of the movement called Humanism, which merely represented the translation of Jewish and Christian dogma into secular symbolism: social role and hierarchy were removed in favor of egalitarianism, humanity was artificially uplifted above nature through the appeal of sentiment, and the importance of the "individual" became defined.
As a whole, black metal finds extreme fault with Judeo-Christian thought in all of its forms. However, not all black metal bands focus specifically on every single aspect of it. Depending on their main theme or subject matter, a black metal band may only devote their attention to one major Judeo-Christian ideal. Yet, in the end, its understood that if their goal were to be achieved, the religions themselves must be overthrown entirely.
The submission of one's personal will to the will of an external force, "God," is one of the primary ideals of Judeo-Christianity that black metal finds abhorrent. Overall, black metal believes that the world is irrational and actions, beings, and lives have no "meaning" as assigned by an outside actor like God, but rather, that they gain meaning through their own willpower. With Christianity, one must follow a certain set of rules or be punished for all eternity; there are no options for living aside from the teachings of scripture. As a result, life is linear. Black metal rejects that idea.
Black metal also abolishes the definition of "sin" and the dualist morality associated with it. Their analysis is this: that in Judeo-Christianity, actions are binarily classified as either "good," i.e. they follow the will of God (or in the case of secularized Christian ideals like liberalism, God is replaced by normality) whether arbitrary or not, or "sins," which are always "evil" despite any positive outcome that might arise from doing them. From this type of thinking comes a self-congratulatory notion that by doing "good," one is superior to those who do "evil," even if they are more intelligent, more heroic, or more natural in their approach to life. For this reason, Judeo-Christian moralism is called an "absolutist" system of thought, in that the dualistic definition of morality becomes the ultimate determiner of the merit of all things. Black metal often promotes the idea that actions and decisions should be based on the merit of their necessity, function, or whether they're the most natural choices for the system in which they occur. Additionally, black metallers (and many other metal writers alike) typically see Judeo-Christians as hypocrites, who are quick to judge and who claim moral superiority, but are blind to their own vanity and passive aggression. Although that isnt a hard and fast rule: some black metallers believe that followers of Judeo-Christian religions are simply sleeping, waiting to be awakened through philosophical enlightenment.
Black metal also rails against the concepts of mortification and repentance. Christians repent before the will of their God: they submit themselves to it so that they can remove the responsibility of "sin" and ultimately, enter Heaven. Thus, they keep themselves mortified, fearful of their own actions and the consequences of breaking the will of God. Black metal contends that there should be no need to grovel before God, begging for forgiveness, because there is no God: life is the master of its own destiny, pride is natural, and death is the only absolute, for which there can be no avoidance.
The artificial elevation of humankind above nature is another important Judeo-Christian concept that black metal seeks to topple. This way of thinking isn't unique to the religious practices alone, but during the "Enlightened" age and the Humanist movement, it found its way into secular thought as well. It comes from the idea that human beings are blessed with "souls," which makes them God's children and gives them ultimate dominion over the earth and the creatures on it. Black metal understands this kind of humanism to be extremely dangerous, since it has led to the overwhelming wanton destruction of nature. Many black metal bands realize that fear of nature is a normal human response; they charge that nature should be respected for its beauty and timelessness, but should also be understood for its violence and not expected to be "fair" in its dealings with mankind.
Egalitarianism is the philosophy that the inequalities among people should be artificially removed. This idea comes directly from Christianity--"there is neither Jew nor Greek, there is neither slave nor free man, there is neither male nor female; for you are all one in Christ Jesus"--but was popularized by Humanism, which tried to destroy the social hierachies of the past by spreading the concept that everyone was a unique individual, and so are all equal. Its black metal's common position that egalitarianism is motivated by revenge by the weak against the strong, and that the only real reason it remains socially enforced is because it gives the equalizers more power. Black metal opposes egality on the pretenses that it lowers everyone to the worst possible level, and it promotes the revival of naturalism, survival of the fittest, or old-world social hierarchicalism in its stead, which are seen as healthier systems for all involved.
Lastly, black metal's hatred for Judeo-Christianity gets a significant amount of its motivation from history. During the middle-ages, many of the native populations of Europe were forcefully Christianized by invading crusaders. Conversion by swordpoint was a common practice, and as a result, many ancient tribes and cultures, especially those from Scandinavian and Germanic populations, were destroyed. Black metallers see Christianity as an alien religion that belongs in the Middle-East, not in Europe, and in claiming the need for vengeance against the Church, advocate the utter revival of old pre-Christian "heathen" ways, which are seen as stronger, more natural ideals for their people.