'Do Not Harden Your Hearts' in the Bible

do not harden your hearts, as in the provocation, like as in the day of the trial in the wilderness,

while it is said, "Today if you will hear his voice, do not harden your hearts, as in the rebellion."

he again defines a certain day, "Today," saying through David so long a time afterward (just as has been said), "Today if you will hear his voice, do not harden your hearts."