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Study Dictionary
Calling
Calling [EBD]
a profession, or as we usually say, a vocation (1 Cor. 7:20). The "hope of your calling" in Eph. 4:4 is the hope resulting from your being called into the kingdom of God.
CALLING [ISBE]
CALLING - kol'-ing (klesis, from kaleo, "I call"): Is a New Testament expression. The word is used chiefly by Paul, though the idea and term are found also elsewhere. It has a definite, technical sense, the invitation given to men by God to accept salvation in His kingdom through Jesus Christ. This invitation is given outwardly by the preaching of the gospel, inwardly by the work of the Holy Spirit. With reference to Israel, it is on the part of God irrevocable, not repented of. Having in His eternal counsel called this people, He entrusted them with great gifts, and because He did thus enrich them, He also, in the course of time, summoned them to fulfill the task of initiating the world into the way of salvation, and of preparing salvation for the world. Therefore, He will not desert His people, for He Will not revoke that call (Rom 11:29). This calling is high or upward, in Christ, that is, made in heaven by God on account of Christ and calling man to heaven (Phil 3:14). Similarly it is a heavenly calling (Heb 3:1); also a holy calling, holy in aim, means, and end (2 Tim 1:9). Christians are urged to walk worthy of this calling (Eph 4:1) (the American Standard Revised Version and the Revised Version (British and American), but the King James Version has "vocation"). In it there is hope; it is the inspirer of hope, and furnishes for hope its supreme object (Eph 4:4). Men are exhorted so to live that God will count them worthy of their calling (2 Thess 1:11). They are also urged to make their calling and election sure (2 Pet 1:10). See ELECTION. There is a somewhat peculiar use of the word in 1 Cor 1:26 and 7:20, namely, that condition of life in which men were when God called them, not many of them wise after the flesh, not many mighty, not many noble, some circumcised, some uncircumcised, some bond, some free, some male, some female, some married, some unmarried.George Henry Trever
Also see definition of "Calling" in Word Study