Surety (Noun) - Vine's Expository Dictionary of New Testament Words
Surety (Noun)
[ 1,,G1450, enguos ]primarily signifies bail," the bail who personally answers for anyone, whether with his life or his property (to be distinguished from mesites, "a mediator"); it is used in Hebrews 7:22, "(by so much also hath Jesus become) the Surety (of a better covenant)," referring to the abiding and unchanging character of His Melchizdek priesthood, by reason of which His suretyship is established by God's oath (Hebrews 7:20-Hebrews 7:21). As the Surety, He is the Personal guarantee of the terms of the new and better covenant, secured on the ground of His perfect sacrifice (Hebrews 7:27).