'Assurance' in the Bible

and thy life shall hang in doubt before thee; and thou shalt fear night and day, and shalt have no assurance of thy life.

Yet God preserveth the mighty by his power: He riseth up that hath no assurance of life.

inasmuch as he hath appointed a day in which he will judge the world in righteousness by the man whom he hath ordained; whereof he hath given assurance unto all men, in that he hath raised him from the dead.

that their hearts may be comforted, they being knit together in love, and unto all riches of the full assurance of understanding, that they may know the mystery of God, even Christ,

how that our gospel came not unto you in word only, but also in power, and in the Holy Spirit, and in much assurance; even as ye know what manner of men we showed ourselves toward you for your sake.

Now faith is assurance of things hoped for, a conviction of things not seen.