For the word of God is living and effectual and more piercing than any two edged sword; and reaching unto the division of the soul and the spirit, of the joints also and the marrow: and is a discerner of the thoughts and intents of the heart.
Hebrews 4:10 For he that is entered into his rest, the same also hath rested from his works, as God did from his.
Hebrews 4:11 Let us hasten therefore to enter into that rest: lest any man fall into the same example of unbelief.
Hebrews 4:12 For the word of God is living and effectual and more piercing than any two edged sword; and reaching unto the division of the soul and the spirit, of the joints also and the marrow: and is a discerner of the thoughts and intents of the heart.
Hebrews 4:13 Neither is there any creature invisible in his sight: but all things are naked and open to his eyes, to whom our speech is.
Hebrews 4:14 Having therefore a great high priest that hath passed into the heavens, Jesus the Son of God: let us hold fast our confession.
The verse centers on "Spirit", "word", "living", "effectual", "piercing", "than", "edged", and "sword". It is saying that the verse draws attention to "Spirit" and "word", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 11's "Let us hasten therefore to enter into..." into verse 13's "Neither is there any creature invisible in...", so "Spirit" and "word" belong inside that flow. In Hebrews context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "Spirit" and "word" with trust shaped by these words, not by a vague optimism outside the passage.