Good day KJV1611,
The above scripture is one of many of the most misinterpreted scriptures. Please consider the following:
Matt.16:28
"Truly I tell you, some who are standing here will not taste death until they see the Son of Man coming in His kingdom.”
Mark 9:2
"Truly I tell you, there are some standing here who will not taste death until they see the kingdom of God arrive with power.”
Luke 9:27
"But I tell you truthfully, some who are standing here will not taste death until they see the kingdom of God.”
As you can see from the three instances in red in the three gospels differ slightly, but they are all referring to the same event. Most people when they read this scripture immediately assume that Jesus is talking about his return, which as we will find out is a false assumption.
Below is Luke's account:
"But I tell you truthfully, some who are standing here will not taste death until they see the kingdom of God. About eight days after Jesus had said these things, He took Peter, John, and James, and went up on a mountain to pray. And as He was praying, the appearance of His face changed, and His clothes became radiantly white."
So, Jesus says "there are some here who will not taste of death until they see the kingdom of God.
The next verse continues with "about eight days after Jesus had said this," which infers that the information in the next verse is related to what Jesus said about those not tasting death.
The next verse then states that Jesus took with him Peter, John and James, which are those in the verse who were standing there who would not taste of death.
Following that, the verse states that Jesus face changed and his clothes became radiantly white. Peter, John and James witnessed Jesus transform into His glorified state, which is what he meant when he said "that those standing there would not taste of death until they see the Son of Man coming in kingdom. Jesus was not inferring that those standing there would see him return to the earth. He was referring to them seeing him in his glorified state.
As an example of the phrase used in Luke's version "until they see the kingdom of God," let's look at another verse that uses that same phrase:
"And if I drive out demons by Beelzebul, by whom do your people drive them out? So then, they will be your judges. But if it is by the Spirit of God that I drive out demons, then the kingdom of God has come upon you."
As you can see from the scripture above, when Jesus said "the kingdom of God has come upon you" it was not in regards to his returning to the earth, but was referring to His casting out demons by the power of the Holy Spirit.
In conclusion, Peter, John and James were those who are standing there who would not taste of death until they saw the Son of man coming in his kingdom, which was fulfilled a week later when they saw him transform into his glorified state.
I truly hope you find this beneficial, because it is the truth what Jesus was referring to.