Although not stated verbatim, the concept of separation of church and state has been associated with the US constitution. This is to help enforce our first amendment right, freedom of religion.
Yet some public officials and politicians often use religious texts (mostly the Bible) and beliefs to justify their actions. Why this does not clash with freedom of religion?
As an example, Sessions cited the Bible to defend immigration policies resulting in family separations
You seem to be well aware of the First Amendment, the right to free speech and constitutional bar on the establishment of a religion.
The Constitution does not prevent any lawmaker or member of the executive from using their religious beliefs to justify their actions. Indeed the First Amendment would class this as protected free speech.
How can you have freedom of religion if people cannot cite their religious texts in explaining how they came to decisions? As already noted, such a ban would violate both freedom of religion and freedom of speech.
Should murder and thievery be allowed because religions prohibit them? Just because a religion has an opinion on something doesn't take it outside regulation by the government.
In the United States, the Constitution protects against the establishment of a religion. This means that the government cannot tell you what religion to worship nor how you worship.
I would also point out that Jeff Sessions' comments were in response to other comments. From the transcript:
Let me take an aside to discuss concerns raised by our church friends about separating families. Many of the criticisms raised in recent days are not fair or logical and some are contrary to law.
First- illegal entry into the United States is a crime—as it should be. Persons who violate the law of our nation are subject to prosecution. I would cite you to the Apostle Paul and his clear and wise command in Romans 13, to obey the laws of the government because God has ordained them for the purpose of order.
What happens is that people say something along the lines of: How do you, as a Christian, justify ... Sessions was answering that question, how he squares his personal faith with his actions as Attorney General. He did so with a rather generic homily on obeying the lawful government.
Sessions was responding to the idea that he should enforce the law differently because of religion. He was saying that even if you believed that, his religion (and presumably that of his listeners) said to obey the lawful government.
"Separation of church and state" usually means that politicians don't have to take religious tenets into account when making decisions. It does not mean that they must ignore them.
It further means that "The Church" (or any other religious organization) has no special political privileges and powers to directly make political decisions or appoint political officials. But freedom of religion and freedom of speech means that "The Church" does still have indirect political influence due to their ability to influence the opinions of those willing to listen to them. Just like any other non-governmental organization has indirect political influence on their sympathizers.
Many politicians got democratically elected in part because they promised to make religious tenets a part of their decision making. A good example is US Vice President Mike Pence who repeatedly described himself as "A Christian, a Conservative and a Republican, in that order". The constituents who voted politicians into office who made such promises now expect them to live up to them and make politics according to the religious values they claimed to support.
What the US constitution forbids these politicians from doing is described in the first amendment:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, [...]
That means even if politicians got voted into office for their promise to make decisions based on their religious beliefs, they are not allowed to use laws to force people to convert to their religion or prohibit people from exercising different religions. But making political decisions about things other than religious worship and justifying these decisions with religious tenets is neither.
Further, prohibiting politicians from stating their religious beliefs and how they affect their decision making would be an infraction on the politicians' freedom of religion rights.
how can the bible be used as justification for certain actions taken by the government?
"the bible" was not used for
justification for certain actions taken by the government
in the current instance.
The decision of so-called "zero-tolerance" as to the subject matter is a policy, not based on religion or "the bible".
The individual appararently wanted to include the term "the bible" in their statement because the individual is speaking to a specific audience (political constituency) which identify themselves with "the bible".
For an individual whom does not believe in the stories in "the bible", that part of the statement is irrelevant, save for the recognition that that part of the stump speech was intended for a specific political audience; or that the individual themselves believes in the stories in "the bible", which is still irrelevant to the substance of the officially stated policy objectives.
The statement is mild at best within the realm usage of "the bible" as a signal to particular political constituents in the U.S.
What matters politically is the actual policy.
The US Constitution is the establishing law authorizing all other legal proceedings in the United States. It's not a moral code. It's not meant to be a moral code. In fact, by separating church from state, it explicitly puts the onus for establishing one's own moral code on each individual.
Clearly, Sessions was demonstrating that his sense of morality is informed by the Bible. He wasn't citing the Bible as a legal document, but rather trying to assuage the fears that his actions were detached from morality.
The "separation of church and state" is one of the most misunderstood parts of the U.S. Constitution. The relevant text is found in the first sentence of the First Amendment, and it states:
"Congress shall make no law respecting an establishment of religion, nor prohibiting the free exercise thereof... "
The first part of the sentence is the Establishment clause, and the second part is the Free exercise clause.
All it means is that the government may not set up an official state religion or pass any laws that would have the same effect. Likewise, it also may not pass laws that prevent you from expressing your own religious devotion in whatever manner you choose.
The First Amendment requires the government to be neutral with regard to religion, and further requires that neutrality to be inclusive of religious faiths, not exclusive of them. In fact, the government is required to consider religious faith when it acts, weighing how to accomplish its goals in a manner that restricts religious expression to the minimum extent possible.
Now, on to Jeff Sessions' comments...
There are two Jeff Sessions at play here. One of them is Jeff Sessions, Attorney General of the United States, and the other is Jeff Sessions, a man from Alabama.
AG Jeff Sessions is required by oath to uphold the Constitution in his official capacity as Attorney General, including the Establishment and Free exercise clauses. Citizen Jeff Sessions is just an ordinary guy who is free to express whatever religious beliefs he wants.
As a man, Jeff Sessions is an evangelical Christian from a heavily evangelical state (they don't call it the Bible Belt for nothing). His religious faith informs and guides his thinking and worldview as Attorney General. Sometimes his faith and his job are in agreement with each other. Sometimes they are not. But in this particular case they are, and this is what he was saying.
It is not the policy of the United States government to use the Bible or any other religious text as the basis of law. However, sometimes the law aligns with religious teaching, and that's perfectly understandable, since the law and religion both ultimately serve (or at least attempt to serve) a moral purpose.
You can separate church and state all you want, but you cannot separate religion from politics – especially in a country like the US where religion is a much bigger part of the daily lives of its citizenry than for other western democracies.
A facet not noted in other answers...
Some religions are contrary to each other, and have mutually exclusive, or even universally exclusive tenets. Suppose religion X teaches A, and religion Y teaches not-A. Now assume the question of A or not-A has some unavoidable political application.
A politician with any policy regarding A must necessarily at times either please adherents of either X or Y, and likewise displease the other.
It would not logically follow from policy A that the politician was in fact an adherent of X, anymore everyone following a Catholic Priest at a busy crosswalk must therefore be a catholic. A politician might seem faithful to X or Y while pursing an A or not-A policy, but it would not necessarily follow that they are faithful.
On the other hand, there are nigh-ancient traditions for politicians who are not religious but who contrive to seem religious, as Machiavelli infamously wrote:
And you are to understand that a Prince, and most of all a new Prince, cannot observe all those rules of conduct in respect whereof men are accounted good, being often forced, in order to preserve his Princedom, to act in opposition to good faith, charity, humanity, and religion. He must therefore keep his mind ready to shift as the winds and tides of Fortune turn, and, as I have already said, he ought not to quit good courses if he can help it, but should know how to follow evil courses if he must.
A Prince should therefore be very careful that nothing ever escapes his lips which is not replete with the five qualities above named, so that to see and hear him, one would think him the embodiment of mercy, good faith, integrity, humanity, and religion. And there is no virtue which it is more necessary for him to seem to possess than this last; because men in general judge rather by the eye than by the hand, for every one can see but few can touch. Every one sees what you seem, but few know what you are, and these few dare not oppose themselves to the opinion of the many who have the majesty of the State to back them up.
(Mr. Sessions may have espoused religious dogma for the purpose of spectacle, (to flatter his base and rattle his opposition), rather than from motives of personal or general interest. That any religious justification for policy is relevant, rather than incidental, seems a dubious prospect in such light.)
For politicians so inclined, the U.S. Constitution itself comprises a kind of virtual sacred text, so that Machiavelli's advice might be applied to it as well. That is, a politician who really was a religious dogmatist might conceal that fact if facing a secular or multi-cultural majority, and instead pretend to be a devout Constitutionalist, and paint every tyrannical stratagem in bright Constitutional colors.
No, that is not a violation of separation between Church and State.
While some politicians might be religious, the fact that they are democratically elected in a secular manner, and have to follow democratically established procedures to pass laws, suggests the firewall between Church and State remains entact.
Here are some examples that actually violates the separation of Church and State:
