How do we know that God's calling for Christians is true?

The truth of God's calling is affirmed in Scripture, as seen in passages like 2 Timothy 1:9, where Paul states that God has saved us and called us with a holy calling, not according to our works but according to His own purpose. This divine calling is supported by the transformation of believers, who are being restored to the dignity lost through sin. The assurance of salvation and the internal work of the Holy Spirit confirm that believers are indeed chosen and called according to God's eternal purpose, reinforcing the absolute truth of their calling.