7So, as the Holy Spirit says: "Today, if you hear his voice, 8 do not harden your hearts as you did in the rebellion, during the time of testing in the wilderness, ...
-- Hebrews 3:7-8 (NIV)
Why is "Today" capitalized in Hebrews 3, verses 7, 13 and 15?
Is "Today" another word for God?
Is the time short for us to change?
How is that we harden our hearts?
Is it sin that we don't ask to take from us the hardening of our hearts?
Answering just your question, "How is it that we harden our hearts ?".
I understand hamartia, sin, to be the negation of martus [a/martus] which is the contradiction of testimony or witness. It is not the absence of a witness which would be Paul's word, anamarturos, "without witness", which he used when speaking to the Athenians.
So, in context in this passage, the hardening of the heart - in a sinful way - would be to contradict the passages from the Old Testament which are being quoted by the writer.
Heb. 3:7, 13, & 15 are quoting from Psa. 95:7-11. As it is a quote from the Holy Spirit, the AMP and the NASB versions capitalize the entire section quoted from Psa. 95 for emphasis. In many of the English translations of Psa. 95:7 the word "Today" is capitalized as a new sentence with an imperative command.
"For He is our God, And we are the people of His pasture, And the sheep of His hand. Today, if you will hear His voice:" - NKJV
"For He is our God, And we are the people of His pasture and the sheep of His hand. Today, if you would hear His voice," - NASB
"For he is our God, And we are the people of his pasture, and the sheep of his hand. To-day, oh that ye would hear his voice!" - ASV
The urgency is "Listen to Me NOW" while you have the time. He is calling today, and we only have today. Yesterday is past and gone. Tomorrow may never be. So, we have this moment in time to hear Him and to answer His call. Today.
Looking at the OP's verses has brought to light a distinct difference between Today (Gr. sEmeron) and Day (Gr. hEmera).
sEmeron (Strong's #4594) - found 41x in 40 vv. Neuter. ((Time/period of Grace))
hEmera - (Strong's #2250) - found 389x in 366 vv. Feminine.
Matt. 6:34 - Interlinear - "...sufficient to-the day (hEmera) the evil of-her.
Jamieson-Fausset-Brown Bible Commentary (For Heb. 3:13 on Bible Hub.)
"...while it is called To-day—while the "to-day" lasts (the day of grace, Lu 4:21, before the coming of the day of glory and judgment at Christ's coming, Heb 10:25, 37). To-morrow is the day when idle men work, and fools repent. To-morrow is Satan's to-day; he cares not what good resolutions you form, if only you fix them for to-morrow."
Good eye of OP for at least seeing something was unusual about those verses. Thanks so much for this major find!
