In John 5:24-29 Jesus speaks of two resurrections; one that began with His teaching, and one that is still in the future.
The first one is the spiritual resurrection of those who hear the words of Christ and believe (v. 24-25). Because of sin we are all spiritually dead without Christ, but if we hear His voice and follow His words in faith, we pass from death unto life.
The second resurrection is a day that is still coming (v. 28-29). That day all will hear the voice of Christ, and all will obediently come forth from the grave to be judged. The outcome that awaits at this resurrection depends on whether you have taken part in the first resurrection.
We choose whether to hear His voice now, but there is coming a day when there will be no choice in the matter. We must make that choice here and now.