Hebrews 4:12 (BSB)

For the word of God is living and active. Sharper than any double-edged sword, it pierces even to dividing soul and spirit, joints and marrow. It judges the thoughts and intentions of the heart.

From Hebrews 4. Also in the ESV.

Commentary on Hebrews 4:12

• John Calvin (Reformed), Calvin's Commentaries on Hebrews 4:12: 12. For the word of God is quick, or living, etc. What he says here of the efficacy or power of the word, he says it, that they might know, that it could not be despised with impunity, as though he had said, “Whenever the Lord addresses us by his word, he deals seriously with us, in order that he may touch all our inmost...
• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Hebrews 4:11-16: In this latter part of the chapter the apostle concludes, first, with a serious repeated exhortation, and then with proper and powerful motives. I. Here we have a serious exhortation: Let us labour therefore to enter into that rest, Heb 4:11. Observe, 1. The end proposed - rest spiritual and eternal, the rest of grace here and glory hereafter - in Christ on earth, with Christ in heaven. 2.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Hebrews 4:12: Neither is there any creature that is not manifest in his sight,.... Christ is the Lord God omniscient; there is no creature, in general, rational, or irrational, animate or inanimate, but what are known to him, and seen by him; for all creatures are made, and upheld by him, and he is omnipresent; and in particular, there is no man but is manifest to him...
• Albert Barnes (Presbyterian), Barnes' New Testament Notes on Hebrews 4:12: Verse 12. For the word of God. The design of this and the following verse is obvious. It is to show that we cannot escape the notice of God; that all insincerity, unbelief, hypocrisy, will be detected by him; and that since our hearts are perfectly open before him, we should be sincere, and should not attempt to deceive him.