But exhort one another daily
In order to prevent unbelief and apostasy. The phrase is sometimes rendered, "comfort one another", or, "yourselves together", as in ( 1 Thessalonians 5:11 ) which the saints may do, by discoursing together about divine things; by praying together; by instructing one another in the doctrines of the Gospel; by putting one another in mind of the covenant of grace, and its promises; and by observing the near approach of everlasting happiness with Christ. And though the business of exhortation greatly belongs to ministers of the word, yet it ought not to be neglected by private believers; who ought, when it becomes necessary, to exhort one another to prayer; to an attendance on the word and ordinances; to a regard to their conversations; to a close adherence to their profession; and to a believing view and consideration of Christ, the apostle and high priest of it; and to a due concern for his truth and interest: and this should be done in love, with good and consolatory words, and in things, in which the saints are concerned, and do themselves regard; and it is an affair which requires prudence and faithfulness; and supposes that God's own people may be dull, heavy, and sluggish; and this is to be done "daily", every day, as often as there is an occasion, and an opportunity for it; and
while it is called today;
while the Gospel dispensation continues; or while the time of life lasts. This shows that the phrase "today", in ( Psalms 95:7 ) did not respect David's time only. The Syriac version renders it, "until that day which is called today": until the everlasting day appears, when there will be no need of such exhortations, nor any danger of what follows:
lest any of you be hardened through the deceitfulness of sin;
actual sin, which is a transgression of the law; every sin is of an hardening nature, and by being often committed, an habit is contracted, and a callousness brought upon the heart and conscience; or the corruption of nature, indwelling sin, may be meant; an evil and a corrupt heart, which deceives through promises of pleasure, or profit to a man's self, or of secrecy and impunity; it suggests the power a man has to repent at pleasure, and the mercy of God, by which means the man is drawn in to it, and by frequent repeating it, grows hardened in it.