8 do not harden your hearts as you did in the rebellion, during the time of testing in the wilderness,

Read Hebrews 3:8 Using Other Translations

Harden not your hearts, as in the provocation, in the day of temptation in the wilderness:
do not harden your hearts as in the rebellion, on the day of testing in the wilderness,
don’t harden your hearts as Israel did when they rebelled, when they tested me in the wilderness.