Today I worked through Hebrews 4, in which the writer chastised his original readers for their failure and disobedience. Although the original readers knew that Christ had made the ultimate atonement for sin, they refused to trust the sufficiency of His work on the cross. The implicit insistence against resting in Christ's shed blood constituted the disobedience of unbelief.
21st Century evangelicals can commit the same sin of unbelief by turning to various human inventions to augment their faith. Any expectation that we can contribute to our salvation through sacraments, Charismatic practices, good works, dietary rules or whatever else our inflated egos devise rebels against obedient faith demonstrates willful unbelief. Therefore, the following warning applies to us just as certainly as it applied to the First Century Jewish Christians.
11 Let us therefore strive to enter that rest, so that no one may fall by the same sort of disobedience. 12 For the word of God is living and active, sharper than any two-edged sword, piercing to the division of soul and of spirit, of joints and of marrow, and discerning the thoughts and intentions of the heart. 13 And no creature is hidden from his sight, but all are naked and exposed to the eyes of him to whom we must give account. ~~Hebrews 4:11-13 (ESV)
Through Scripture, the Lord will both expose and judge the refusal to obey God by resting in what He's done. (He will expose and judge other expressions of disobedience as well.) We may convince other people--and even ourselves--of our spirituality, but the Lord will judge us by His Word, laying us naked before Him. I suppose so many people adulterate or hate the Bible for this very reason.
The Lord, however, doesn't leave His elect stranded in judgement. After all, true faith finds rest in Christ, trusting His gentle grace. And so, guided by the Holy Spirit, the writer of Hebrews brings our gaze back to Jesus.
14 Since then we have a great high priest who has passed through the heavens, Jesus, the Son of God, let us hold fast our confession. 15 For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin. 16 Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need. ~~Hebrews 4:14-16 (ESV)