Dictionary of Biblical Words:
Man’s blood when shed cries to God for vengeance (Gen. 4), and defiles the land (Num. 35:33). The blood of Christ speaks better things, and enables God in righteousness to show grace to sinners. It also cleanses from all sin (1 John 1:7). By it we have forgiveness (Eph. 1:7), justification (Rom. 5:9), and entrance into the holiest (Heb. 10:19). Blood is the life of the flesh, and was forbidden to man (Gen. 9, Levit. 17., Acts 15). Now, however, having died with Christ (Rom. 6), we can in figure drink the blood of Christ, who is our life in resurrection. It is remarkable that the death of Christ is seldom spoken of in connection with our salvation, whereas the “blood” is constantly referred to. We have redemption, peace, remission, and access by the blood; by it we are justified, made nigh, purged, cleansed, and sanctified.
From Anstey’s Doctrinal Definitions:
The blood of Christ stands as a token of the work of atonement being made for the glory of God and for the blessing of man (John 19:34). Scripture speaks of Christ’s blood being “shed” for believers, which is God’s provision for them to be saved (Matt. 26:28; Mark 14:24; Luke 22:20). Scripture also speaks of the blood of Christ being “sprinkled” on the hearts of believers, which refers to faith’s appropriation of the finished work of Christ on the cross (Heb. 10:22; 12:24; 1 Peter 1:2).
The New Testament speaks of at least twelve things that the blood of Christ does:
• It makes atonement—propitiation (Rom. 3:25) and substitution (Matt. 26:28).
• It purchases all things and persons (Acts 20:28; Rev. 5:9).
• It effects redemption (Rom. 3:24; 1 Peter 1:18-19).
• It grants forgiveness (Eph. 1:7).
• It produces a purged conscience (Heb. 9:14; 10:2)
• It gives boldness to enter God’s presence (Heb. 10:19).
• It effects justification (Rom. 5:9).
• It makes peace (Col. 1:20).
• It brings us nigh to God—reconciliation (Eph. 2:13).
• It sanctifies us (Heb. 10:29; 13:12).
• It washes or cleanses us (1 John 1:7; Rev. 1:5; 7:14).
• It gives the title to final victory over Satan (Rev. 12:11).