Yehezkiel 18:31

18:31 Throw away all your sins you have committed and fashion yourselves a new heart and a new spirit! ¹  Why should you die, O house of Israel?

Yehezkiel 36:26

36:26 I will give you a new heart, and I will put a new spirit within you. I will remove the heart of stone ²  from your body and give you a heart of flesh. ³ 

[18:31]  ¹ sn In Ezek 11:19, 36:26 the new heart and new spirit are promised as future blessings.

[36:26]  ² sn That is, a heart which symbolizes a will that is stubborn and unresponsive (see 1 Sam 25:37). In Rabbinic literature a “stone” was associated with an evil inclination (b. Sukkah 52a).

[36:26]  ³ sn That is, a heart which symbolizes a will that is responsive and obedient to God.