How do we know faith in Christ is essential for salvation?

Faith in Christ is the supreme necessity for salvation, highlighted by Christ's warning that 'he that believes not shall be damned.' This indicates that merely being baptized or outwardly conforming to religious practices is insufficient for salvation. The individual must possess saving faith, which involves recognizing one's sinfulness and actively placing trust in Christ for redemption. This crucial element of faith distinguishes genuine believers from those lost in the visible church.