Take care, brethren, that there not be in any one of you an evil, unbelieving heart that falls away from the living God. But encourage one another day after day, as long as it is still called “Today,” so that none of you will be hardened by the deceitfulness of sin. For we have become partakers of Christ, if we hold fast the beginning of our assurance firm until the end, while it is said, “Today if you hear His voice, Do not harden your hearts, as when they provoked Me.” (Hebrews 3:12-15, NASB)
The text above is from the book of Hebrews, author unknown. The theme of this passage is the encouragement of brothers and sisters in Christ so that they do not fall away from the promise that awaits them. Since “we have become partakers of Christ,” we shouldn’t be involved in sin. “But encourage one another day after day, as long as it is still called ‘Today.'” Why? “So that none of [us] will be hardened by the deceitfulness of sin.” The author tells us to encourage each other today. We are not to wait until tomorrow, but to do it today. Tomorrow might be too late!
https://bible.knowing-jesus.com/Hebrews/3/13
The last quotation in the passage refers to the Israelites when they were wandering through the Sinai Peninsula enroute to the Promised Land. They hardened their hearts to the point where God vowed that none of them would enter His rest in Israel, except for Joshua and Caleb, and the sons and daughters of the sinners. The warning here is for us to not do the same. Instead, we are to encourage each other so as not to engage in sin.
We followers of Jesus are to encourage each other “Today,” and “day after day.” It seems we’re never to stop. The objective is to ensure “we” don’t lose the hope of God’s rest that awaits us in Paradise. That would be a shame.