“I tell you the truth, a time is coming and has now come when the dead will hear the voice of the son of God and those who hear will live.” (John 5:25)

Many sectarian teachers interpret Jesus' statement here as foretelling some time in the distant future when Jesus will come again at the end of the world and save all those who have died in the meantime.

Now let's look at this practically. 

This means that, if say the end of the world was tomorrow, there would have to be a location where billions upon billions of those who called themselves Christians at some point in the past 2,000 years would have to wait.

Today alone, there are some 2 billion supposed Christians in the world. If we add this to all those who have lived and died over the past 2,000 years this could add up to well over a trillion people. And where are these people all waiting? In their graves? Certainly their bodies have decomposed.

Or in some kind of purgatory state? 

And where is such a purgatory state located?

This is all simply imaginative speculation put together by those who have no understanding of Jesus' teachings.

Here Jesus uses the word "dead" translated from the Greek word νεκρός (nekros) - which can mean "without life" but its metaphorical meaning according to the Greek lexicon is "spiritually dead."

The simple fact is that Jesus' use of the word "dead" is simply an analogy for a person who has rejected their relationship with the Supreme Being. This is confirmed by this statement made by Jesus:
“Follow me, and let the dead bury their own dead.” (Matt. 8:22)
In this statement by Jesus we can see that those who are burying their dead are not physically dead, or how else could they bury a dead body? The type of "dead" person here is someone who is ignorant of the Truth of their relationship with God.

This is also confirmed as Jesus says here that those who hear and understand his teachings will become enlightened: "those who hear will live.” Here again, Jesus uses"live" not in the literal physical sense. The word "live" is describing someone who has become spiritually enlightened, and spiritually fulfilled as a result. 

"Time is coming" 

So when is that "time is coming" Jesus is referring to? The hint for this is that he says right after this phrase, "and has now come" - from the Greek phrase, καὶ νῦν ἐστιν. This indicates that people are able to hear and understand Jesus' teachings at the time he was speaking. And the "time is coming" indicates that others will come to understand his teachings as he teaches to more people and his teachings are spread by his students.

The bottom line is that Jesus often have used analogies because spiritual topics are beyond the physical realm. Yet Jesus' teachings were very practical, as he strived to reach the broadest audience.

Thus Jesus' teachings were practical. Jesus was speaking to those who were hearing him speak. As he spoke about the subject matters regarding our relationship with God, he enlightened people. As those teachings were heard and understood, people became fulfilled. 

How so? Because without our relationship with God there is emptiness. This emptiness (or being "dead") results from self-centeredness. When we live for ourselves, we feel empty. But when we live for the Supreme Being - our Best Friend and Constant Well-wisher - and use our lives to please Him, we become fulfilled. We become "born again." We become "saved."

This is because our natural position is to love and serve the Supreme Being. We may each have the choice to love and serve Him because love requires freedom of choice, but we were still created for the purpose of loving and serving the Supreme Being.

Praise God