What does the 'first shall be last and the last first' mean in the Bible?

'The first shall be last and the last first' serves as a sobering reminder of the nature of God's kingdom as seen in Mark 10:31. This declaration highlights the reversal of human expectations, illustrating that those who may seem prominent or favored in the world's eyes may ultimately be at a disadvantage spiritually. Conversely, those who are humble and recognize their need for God's grace may be exalted. This principle not only applies to the disciples' understanding of their status but also acts as a timeless truth regarding God's sovereign election and grace in salvation. It confronts self-righteousness and beckons believers to embody humility and dependence on God's mercy.