How do we know God's promises for the righteous are true?

The assurance that it shall be well with the righteous comes from the righteousness of Jesus Christ, who represents His people before God. Believers are legally accepted by God due to Christ's obedience and sacrificial death (Romans 5:8). This promise is not contingent on worldly circumstances but is rooted in the faithful character of God who has declared Himself committed to the salvation of His elect. The righteous can be confident in their eternal security because Christ bore all condemnation on their behalf, as stated in Romans 8:1, 'There is therefore now no condemnation for those who are in Christ Jesus.' Thus, regardless of earthly trials, the ultimate outcome for the believer is everlasting life and communion with God.