“Don’t tell anyone what you have seen ...” (Matthew 17:9)

When they looked up, they saw no one except Jesus. As they were coming down the mountain, Jesus instructed them, "Don't tell anyone what you have seen, until the Son of Man has been raised from the dead." (Matthew 17:8-9)

Why does Jesus request their secrecy?

Jesus says this as he, Peter, James, and John were walking down from the mountain after witnessing hearing God’s voice - and after Jesus had spoken with Moses and Elijah.

It is understood from his statement that Jesus knows people may not understand what happened on the mountain very easily, and it could inflame things. As such, Jesus understands that this information is best suited for public consumption later.

This relates to his position as teacher and the fact that the Supreme Being wants to give people the choice to love Him. God doesn't want to force us into accepting Him. He wants that to come out of freedom of choice.

"...until the son of man..."

Remember that "son of man" is a mistranslation of the Greek phrase, υἱὸς τοῦ ἀνθρώπου. The word υἱὸς can only mean "son" in the context of a physical family, and the lexicon confirms that it also relates to a follower or servant ("used to describe one who depends on another or is his follower.")

Furthermore, the word ἀνθρώπου can mean "man," or "mankind" or "humanity."

Thus the more appropriate translation of υἱὸς τοῦ ἀνθρώπου is:

"Servant of Humanity"

This is appropriate because Jesus was serving all of humanity with his teachings.

What does 'raised from the dead' mean?

There is a misunderstanding among sectarian institutions regarding the concept of “raised from the dead.” Most ecclesiastical theologians interpret this statement to mean the three-day disappearance of Jesus’ body, and the sudden appearance of his form to his disciples.

The phrase "raised from the dead" is being translated from the Greek phrase ἐκ νεκρῶν ἐγερθῇ. The word ἐκ means "from." The word means can mean "lifeless" or "dead" when used literally, yes. But metaphorically - which Jesus was speaking, according to the lexicon, the word means "spiritually dead."

And ἐγερθῇ means "to arouse, cause to rise" according to the lexicon.

In other words, Jesus is not talking about himself dying at all. He is speaking of himself "rising" or leaving the physical body and the physical world - the spiritually dead.

Is Jesus talking about himself being dead at some point? No. Jesus did not teach that we die when our body dies. He taught that we are eternal, and we live on after the body dies:
"Do not be afraid of those who kill the body but cannot kill the soul." (Matthew 10:28)
Jesus' Jesus' teachings were found upon the idea that after the death of the body we move on. He also taught that we can return to the spiritual realm should we dedicate ourselves to the Supreme Being.

Certainly, a decomposing dead body cannot return to the spiritual realm.

For hundreds of years, humans have been digging up various remains to study ancient history. Frequently, we will even dig up a grave to study a person’s cause of death. Sometimes we even discover situations where people were buried in fields a few years ago. In every case, we find the human body simply decomposes.

We also find no difference in the decomposition between a so-called Christian and a non-Christian either. All bodies decompose equally once the spirit leaves the body.

To this we can reference another statement describing Jesus' thoughts about the physical world:
“Follow me, and let the dead bury their own dead.” (Matthew 8:22)
Here we see again how Jesus is describing persons who are spiritually dead. They are focused upon the forms and things of the temporary physical world. They are identifying themselves with the physical body, and are thus spiritually dead.

What does it mean to be spiritually dead?

To be spiritually dead means to think this body is "me." We are not these physical bodies, however. We the living spirits temporarily occupying a physical body.

Just as a person sits down within a car, we sit within the vehicle of the physical body.

This temporary physical body is dead matter without the spiritual life force that drives it. When the living spirit leaves the body, the body dies. In other words, the body is animated by the living spirit.

Thus, physical matter is essentially dead without the animation of spiritual life forces. Thus, those who dedicate themselves to the matter of the physical world would functionally be considered spiritually dead.

In the above statement, Jesus is telling his disciples to not reveal what happened until after his body dies and he - the spiritual being - returns to the spiritual world. According to Jesus, being "raised from the dead" is essentially the spirit-person returning to the spiritual realm.

In other words, any of us can become raised from the dead if we have advanced spiritually to the point where we can leave the physical dimension and return to the spiritual realm after the death of our current body.

Otherwise, we are destined to return to the physical dimension in another physical body in order to continue to develop our spiritual consciousness.