How do we know God's promise of righteousness is true?

God's promises, including that of a new heavens and a new earth, are rooted in His immutable nature. As recorded in 2 Peter 3:13, we have assurance of this promise, which has its foundations in God's infallible Word. Further, the concept of righteousness dwelling in the new creation signifies God's ultimate plan to restore order and holiness, reversing the effects of sin that marred His original creation as detailed in Isaiah 65:17. Thus, we can trust the veracity of His promises based on Scripture and God’s faithfulness.