Hebrews 4:7

4:7 So God again ordains a certain day, “Today,” speaking through David after so long a time, as in the words quoted before, “O, that today you would listen as he speaks! Do not harden your hearts.”

Hebrews 10:16

10:16 “This is the covenant that I will establish with them after those days, says the Lord. I will put my laws on their hearts and I will inscribe them on their minds,”

Hebrews 10:22

10:22 let us draw near with a sincere heart in the assurance that faith brings, because we have had our hearts sprinkled clean from an evil conscience and our bodies washed in pure water.