Biblical explanation
Ecclesiastes 9:5-6 is unusually direct: "The dead know not any thing." The passage continues by saying that their love, hatred, and envy have ended and that they no longer participate in the affairs taking place "under the sun." This does not mean God has forgotten the dead. God remembers every person and will resurrect them. Jesus demonstrated this when He called Lazarus from the grave. Lazarus did not return from a conscious heavenly existence with a message about what he had seen. Jesus simply called him out of death (John 11:43-44). If the dead were consciously observing earthly life, passages warning against communication with the dead would be difficult to understand. Deuteronomy 18:10-12 explicitly prohibits attempts to consult the dead or communicate with supposed spirits. The biblical emphasis is instead that God alone holds the future resurrection.
Key takeaway
The great controversy reveals God's character as Christ ministers as our High Priest in the heavenly sanctuary. The dead await the resurrection, Christ's return will be visible and personal, and prophecy calls believers to faithful mission rather than date-setting or fear.