Galatians 3 V 26 For you are all sons of God through faith in Christ Jesus. 27 Forj as many of you as were baptized into Christ have put on Christ. 28 There is neither Jew nor Greek, there is neither slave nor free, there is neither male nor female; for you are all one in Christ Jesus. 29 And if you are Christ’s, then you are Abraham’s seed, and heirs according to the promise.
Romans 8 v16-17
16 The Spirit itself beareth witness with our spirit, that we are the children of God:
17 And if children, then heirs; heirs of God, and joint-heirs with Christ; if so be that we suffer with him, that we may be also glorified together.
Spurgeon
“our right to the divine heritage stands or falls with Christ’s right to the same inheritance. We are co-heirs; if he be truly an heir, so are we; and if he be not, neither are we. Our two interests are intertwined and made one, we have neither of us any heirship apart from the other; we are joint heirs, Christ jointly with us; ourselves jointly with Christ. So, then, it follows that if there be any flaw in the will, so that it be not valid, if it be not rightly signed, sealed, and delivered, then it is no more valid for Christ than it is for us.”
Thanks Richard