How does God's calling relate to assurance of salvation?

The doctrine of God's calling is deeply intertwined with the assurance of salvation. When God effectively calls an individual, He not only initiates their faith but also guarantees their perseverance and ultimate salvation. This assurance is rooted in the fact that those called are 'known' by God, as stated in 1 Corinthians 1:9; 'God is faithful, by whom you were called unto the fellowship of his Son.' This means that the security of the believer rests not on their performance but on the unchanging faithfulness of God who calls them. The promise found in Joshua 23:14 reassures believers that 'not one thing has failed of all the good things which the Lord your God spoke concerning you.' Such promises bolster the believer’s confidence in the eternal security provided through God's sovereign grace.