What does the Bible say about who shall be saved?

According to Mark 13:13, Jesus tells His disciples that 'he that shall endure to the end, the same shall be saved.' This implies that the ones who will ultimately be saved are those whom God has chosen and called to salvation before the foundation of the world, as illustrated in 2 Timothy 1:9, which says, 'He saved us and called us with a holy calling, not according to our works, but according to His own purpose and grace.' This indicates that salvation is not a matter of human decision or action, but entirely an act of God's will and mercy.