How do we know Christ is mighty to save?

Isaiah identifies Christ as 'mighty to save' because He embodies righteousness and strength. This strength was demonstrated in His sacrificial death on Calvary, where He bore the sins of His people, effectively saving them from eternal judgment. The miracle of salvation is grounded in the effectiveness of His atoning work; as affirmed in Romans 3:22-26, it is through faith in Christ’s blood that sinners are declared righteous and saved, highlighting His power to save completely those whom the Father has given to Him.