How do we know the righteousness in white garments is true?

The white garments represent the garments of salvation and the robe of righteousness that believers are given by God. As emphasized in Isaiah 61:10, it is God who clothes His people, signifying that the righteousness needed to stand before Him is not from human effort but is a gift accessed through faith in Christ. Philippians 3:9 reflects this truth, as it emphasizes the desire to be found in Christ, not having our own righteousness but the righteousness from God received through faith.