Why is belief in Jesus Christ crucial for being part of the remnant?

Being part of the remnant is intrinsically linked to belief in Jesus Christ, as He is the fulfillment of God's covenant promises. Romans 10:9 states that confessing with your mouth that Jesus is Lord and believing in your heart that God raised Him from the dead is essential for salvation. This belief acknowledges that salvation comes only through Christ, and it is by grace that we are saved, as mentioned in Ephesians 2:8-9. The remnant is composed of those who recognize their sinfulness and receive the righteousness of Christ by faith. In Christianity, true assurance of salvation is found in trust towards Christ alone, affirming that it is not about what we do but about what Christ has accomplished.