Christians have encouraged each other by passing the message of the Lord's presence on to each other.

The peoples have encouraged one another with reference to their liberties, rights, and privileges.

The "voice of the archangel", as used in this passage, means one with authority, the chief messenger, Christ Jesus himself.

He comes with light and truth, illuminating the minds of men, leading them into greater light which has come upon the end of the age when the shout of encouragement for the rights and liberties of the people and the deliverance of Christians into the kingdom of the Lord has begun throughout the earth.
[463]During this time, then, we should expect the resurrection of those saintly ones who died before the second coming of the Lord; and should expect that these would be awakened out of death and gathered unto the Lord, thus to be forever with him.

And therefore those believers who were alive at his coming, when the time came for their death, would experience an instantaneous change from human to spirit beings.