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Study Dictionary
Forerunner
Forerunner [EBD]
John the Baptist went before our Lord in this character (Mark 1:2, 3). Christ so called (Heb. 6:20) as entering before his people into the holy place as their head and guide.
FORERUNNER [ISBE]
FORERUNNER - for-run'-er (prodromos): This word occurs but once in the Bible: "Whither as a forerunner Jesus entered for us" (Heb 6:20). The word signifies one who comes in advance to a place where the rest are to follow, or one who is sent on before as a scout to take observations. In this sense Christ is our forerunner for He has gone into heaven to prepare a place for His people into which He will eventually lead them. The idea of a forerunner is peculiar to the Christian dispensation. The Old Testament Levitical economy knew nothing of such. The high priest was a representative, not a forerunner: where he led, namely, into the Holy of Holies, the people could not follow. He was not the pioneer of the people; Christ is. Christ goes nowhere but where His people may follow. He is the file-leader (compare Heb 12:2, "the author .... of faith"). He goeth before His people to prepare the way for them, to open the gates of heaven by His atoning blood and priestly intercession. The believer is led into full fellowship with God through Jesus Christ.See also JOHN THE BAPTIST; RUNNER.
William Evans
Also see definition of "Forerunner" in Word Study