What does Psalm 10:18 mean?

Not only will God hear the prayers of the afflicted and encourage them, but He will also bring justice to those who are helpless, abandoned, or abused by others. In ancient cultures, those who were orphaned—the "fatherless"—were incredibly vulnerable, as were widows. Those who are "oppressed" by others includes those abused by authority, government, or others who wield power over them.

Today, many of the Lord's people suffer injustice and oppression at the hands of their persecutors. Difficult as this is to endure, the situation should not surprise them. Jesus predicted that His followers would experience terrible hardship in the world, but He said, "take heart; I have overcome the world" (John 16:33). Someday God will make everything right. He will end the injustice and will wipe away every tear from the eyes of the oppressed (Revelation 7:17). When the Lord executes justice, He will punish the wicked, and they will never terrorize anyone again. In the tribulation period, the beast and the false prophet will launch a reign of terror, but their terror will end when the Lord casts them both alive into the lake of fire (Revelation 19:20).