The Greeks saw death as the end. One might turn inevitable death into an achievement by dying gloriously, but they believed that existence ended at the close of every life span.
A segment of society sought comfort in philosophy. Of these, some said that since death is natural, each person rightly journeys toward it. Some consoled themselves with the idea that people live on in their children. Some argued that death was a welcome end to human struggles and pains in an uncaring universe. Plato advanced the notion that personality, being moral and immaterial, must continue after the death of the body. But those who lived in the world of the first century held no common belief about immortality, and the notion of resurrection was completely foreign to them.
The words for death in the Greek language express and reflect cultural beliefs. Nekros simple means “dead,” or a dead body.” In the Greek culture, nekros conveyed the idea that the dead has become mere matter. Whatever it was that had made the corpse a person and animated the body was gone. The dead had reached that final state that destiny has decreed for all people.
It is striking to see how nekros is used in the New Testament. In over half of the 133 times it is found it is linked with affirmations of resurrection. The New Testament triumphantly announces concerning Jesus that “God raised Him from the dead” (Acts 13:30), but it goes on to promise that there is resurrection ahead for us as well (I Corinthians 15:12-52). Human beings are more than mere matter!
The word thanatos means “death.” In the Gospels it is usually used of the death of Jesus. In Paul’s letters its use focuses on the apostle’s exploration of the meaning of human death…
As expected, the New Testament view of death builds on and expands concepts found in the Old Testament. It stands in bold contrast to the views of the Hellenic world. Death is not simply a biological phenomenon. Death is a theological phenomenon, with impact in the spiritual as well as the physical realm. As for the physically dead, God is well able to raise them (Acts 26:8).
From Expository Dictionary of Bible Words by Lawrence O. Richards, pp. 407 – 408.