How do we know faithfulness is true in God's character?

The assurance of God's faithfulness rests on the attributes of His character, which are immutable. Scripture assures us that God is not man to lie or change His mind (Numbers 23:19). His faithfulness is demonstrated through the covenants He has made with His people, as seen in His promises to Abraham, the Israelites, and ultimately in Christ. God has proven His reliability across generations, confirming that what He decrees will come to pass. Therefore, when we read in 1 Thessalonians 5:24 that 'Faithful is he that calleth you, who also will do it,' we know it is grounded in God's character that cannot fail. This knowledge instills confidence and encourages us to rely on His promises.