"They shall never enter my rest."

St. Paul's Letter to the Hebrews 4:1-13

BRETHREN, let us fear lest any of you be judged to have failed to reach it.
For good news came to us just as to them; but the message which they
heard did not benefit them, because it did not meet with faith in the
hearers. For we who have believed enter that rest, as he has said, "As I
swore in my wrath, 'They shall never enter my rest,"' although his
works were finished from the foundation of the world. For he has
somewhere spoken of the seventh day in this way, "And God rested on the
seventh day from all his works." And again in this place he said, "They
shall never enter my rest." Since therefore it remains for some to
enter it, and those who formerly received the good news failed to enter
because of disobedience, again he sets a certain day, "Today," saying
through David so long afterward, in the words already quoted, "Today,
when you hear his voice, do not harden your hearts." For if Joshua had
given them rest, God would not speak later of another day. So then,
there remains a sabbath rest for the people of God; for whoever enters
God's rest also ceases from his labors as God did from his. Let us
therefore strive to enter that rest, that no one fall by the same sort of
disobedience. For the word of God is living and active, sharper than any
two-edged sword, piercing to the division of soul and spirit, of joints and
marrow, and discerning the thoughts and intentions of the heart. And
before him no creature is hidden, but all are open and laid bare to the
eyes of him with whom we have to do.