Hebrews 4:6 Since therefore it remains that some must enter it, and those to whom it was first preached did not enter because of disobedience, [7] again He designates a certain day, saying in David, “Today,” after such a long time, as it has been said: “Today, if you will hear His voice, do not harden your hearts.”
The allusion to the Jewish Sabbath continues. I stress the “Jewish” Sabbath because Christians do not celebrate the Sabbath. Traditionally, we celebrate the Lord’s Day, which is the first day of the Jewish week, or in modern terminology, Sunday.