Beware, brethren, lest there be in any of you an evil heart of unbelief in departing from the living God; but exhort one another daily, while it is called “Today,” lest any of you be hardened through the deceitfulness of sin. For we have become partakers of Christ if we hold the beginning of our confidence steadfast to the end, while it is said: “Today, if you will hear His voice, Do not harden your hearts as in the rebellion.” (Hebrews 3:12-15 NKJV)
We fight unbelief and doubt by exhorting, and encouraging each other. When you receive a word of encouragement from the brethren receive it as from the Lord. He uses us to speak to each other and this process strengthens both the giver of the word and the receiver. In faith accept that encouragement, for faith comes by hearing the word of God (Rom 10:17). And when you do receive a word from the Lord pass it on and be a part of God’s plan in strengthening the brethren. This helps us to enter and remain in His rest, for we who have believed do enter that rest (Heb 4:3).