Concise Bible Dictionary:
This term is from qadesh, ἁγιάζω “to set apart to sacred purposes, consecrate.” It has various applications in the Old Testament as to days: God sanctified the seventh day on which He rested; it was afterward to be kept holy by the Israelites (Gen. 2:3; Ex. 20:8). As to persons, the whole of the Israelites were sanctified to God (Ex. 19:10,14). The firstborn were further sanctified to God, to be redeemed by the Levites (Ex. 13:2). The priests and Levites were sanctified to the service of God. As to the place and vessels of divine service, the tabernacle and temple, and all the vessels used therein, were devoted to sacred use in the worship of God (Ex. 30:29). We have thus what was suitable in view of God: there was also what was obligatory on the part of those that approached.
The priests, Levites, and people were often called upon to sanctify themselves, to be ceremonially fit to approach God and His sanctuary (Lev. 20:7; Num. 11:18; etc). God declared, “I will be sanctified in them that come nigh Me” (Lev. 10:3): God must be approached with reverence and in separation from what is unsuited to Him.
In the New Testament sanctification has many applications.
1. The thought is twice expressed by the Lord Jesus as to Himself. He spoke of Himself as one “whom the Father hath sanctified, and sent into the world” (John 10:36). He was set apart by the Father for the accomplishment of the purposes of His will. In His prayer for His disciples in John 17 the Lord also says, “For their sakes I sanctify myself.” He set Himself apart in heaven from rights that belonged to Him as man, that His own might be sanctified by the truth. He was sanctified on earth for the Father, He has sanctified Himself in heaven for the saints.
2. Believers are said to be “sanctified through the offering of the body of Jesus Christ once for all” (Rom. 15:16; 1 Cor. 1:2; Heb. 10:10). They are thus saints, “sanctified ones” before God, apart from the life of flesh, a class of persons set apart to God for priestly service (Acts 20:32; Acts 26:18; Rom. 1:7; etc.). In this there is no progress; in effect it implies the most intimate identification with Christ. Such are His brethren. “He that sanctifieth and they who are sanctified are all of one” (Heb. 2:11): the sanctified are “perfected forever” by one offering (Heb. 10:14).
3. But believers are viewed also on the side of obligation and are exhorted to yield their members “servants to righteousness unto holiness” (ἁγιασμός). (Rom. 6:19). God chastens them that they may be partakers of His holiness (Heb. 12:10). Without sanctification no one will see the Lord. In this there is progress; a growing up into Christ in all things (Eph. 4:15). The apostle Paul prayed that the God of peace would sanctify the Thessalonians wholly (1 Thess. 5:23).
4. Sanctification appears to refer to change of association, for the possibility is contemplated of some who had been sanctified treading under foot the Son of God, and treating the blood of the covenant as an unholy or common thing, thus becoming apostates from Christ, and departing from the association in which they had been sanctified (Heb. 10:29).
5. In the existing mixed and corrupt state of Christendom (viewed as a great house, in which are vessels, some to honor and some to dishonor), the obligation to sanctification from evil within the sphere of profession has become obligatory in order that a man may be “a vessel unto honor, sanctified, and meet for the master’s use, and prepared unto every good work” (2 Tim. 2:21).
6. An unbelieving husband or wife is said to be sanctified in the believing partner, and their children are holy (ἅγιος). They can thus dwell together in peace, instead of having to separate from an unbelieving partner, as in Old Testament times (1 Cor. 7:14; compare Ezra 9-10).
7. Food is “sanctified by the word of God and prayer.” Hence “every creature of God is good, and nothing to be refused, if it be received with thanksgiving” (1 Tim. 4:4-5). This is altogether opposed to restrictions prescribed by the law, or which man may impose on the use of what God in His goodness has created for man’s use.
Strong’s Dictionary of Greek Words:
Meaning:
from 40; to make holy, i.e. (ceremonially) purify or consecrate; (mentally) to venerate
KJV Usage:
hallow, be holy, sanctify