Romans 8:16-17

The Spirit Himself testifies and confirms together with our spirit [assuring us] that we [believers] are children of God. And if [we are His] children, [then we are His] heirs also: heirs of God and fellow heirs with Christ [sharing His spiritual blessing and inheritance], if indeed we share in His suffering so that we may also share in His glory. [John 17:24; Gal 3:29; 4:7; Eph 1:3, 11; 3:6; Heb 6:12]