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 12:25

12:25 Take care not to refuse the one who is speaking! For if they did not escape when they refused the one who warned them on earth, how much less shall we, if we reject the one who warns from heaven?