The expression "Everything is sacred" is sometimes presented as the central tenet of pantheism and animism, among other creeds, allegedly with important consequences. This may deserve closer analysis. What could be the meaning and consequences of the statement "Everything is sacred"?
Preparing ground
To prepare the ground and better understand the question, let us examine a few similar expressions, for example:
(1) "Everything is red"
(2) "Everything is wet"
(3) "Everything is bad"
(4) "Everything is good"
Existence and absence of truth-value
Though the statements (1) and (2) are obviously false, their key characteristic, which makes them stand out, is not merely their falsehood, but the fact that we have no trouble objectively ascertaining their falsehood. After asking the speaker of (1) and (2) for definitions of "red" and "wet", we only need to find one example each of a "non-red" and a "non-wet" thing in order to see that (1) and (2) are objectively false. In other words, the statements (1) and (2) are capable of being either objectively true or objectively false, i.e. they can have a truth-value.
Can the statements (3) and (4) also have an objectively ascertainable truth-value? It might be that some people would agree with a statement like "Everything is bad". It is also most likely that there are people who would not agree with the speaker. It is hence impossible to arrive at an objective consensus as to the truth of "Everything is bad" or "Everything is good". In other words, the statements (3) and (4) can not have a truth-value.
The speaker’s state of mind
If (3) and (4) don’t possess a truth-value, what are these statements then actually saying? Well, as they are not saying anything objective about "Everything", but are still uttered by the speaker, then we have to assume that what they are informing us about is the state of mind of the speaker. If I am saying "Everything is bad", then I’m making public my utter pessimism about everything. If I am saying "Everything is good", then I state that I happen to be in a content and happy state of mind.
Sacred concept
Now, let us return to the original statement, "Everything is sacred". Is this statement capable of being true or false, i.e. can it have a truth value? This is perhaps a less obvious matter than our previous examples. We first need to examine the character of the concept "sacred". The term "sacred" is normally not used for "everything" at all. On the contrary, "sacred" is only used for certain very specific things or phenomena, e.g. a "sacred tree", a "sacred animal", a "sacred (holy) man". Hence, before we can apply the term "sacred" to an unusual context, we must analyze its original meaning, the meaning which is derived from its use in specific instances.
Be good
To say "This tree is sacred" means that people should not cut down the tree, but take care of it. "This is a sacred animal" means that we should not hunt or kill this animal, but care for it as best we can. In other words, saying that "X is sacred" is a prescriptive statement, exhorting us to behave decently toward X. A prescriptive statement can not have a truth-value: "Wash your hands!" is obviously neither true nor false. This prescriptive meaning of "sacred" still remains intact, even when "sacred" is used in the unusual context of "everything", as in the statement "Everything is sacred".
So "Everything is sacred" is not a true statement, nor is it false. The meaning of the statement "Everything is sacred" is merely equal to an exhortation: "Behave nicely / benevolently / decently toward everything". Or, expressed differently: "Always be good!"
Admittedly, using the term "sacred" may work as a particularly effective exhortation for superstitious individuals, as it darkly implies sanctions or punishments by some supernatural Entity. Still, its central message for the rest of us is nothing more than the well-meaning, but rather trivial "Always be good".
NOTE: The above is prompted by an exchange of views with Cletus the Foetus, concerning the question How can a thinking, rational adult be a monotheist?.