In his celebrated book Holiness, J.C. Ryle writes:-
Bare simple faith in Christ shall save a man, though he may never attain to assurance; but will it bring him to heaven with strong and abounding consolations? I will concede that it shall land him safe in harbor; but I will not concede that he will enter that harbor in full sail, confident and rejoicing. I would not be surprised if he reaches his desired haven weather-beaten and tempest-tossed, scarcely realizing his own safety, till he opens his eyes in glory.
An inquirer into religion would find more understanding if he made these simple distinctions between faith and assurance. It is all too easy to confuse the two. Faith, let us remember, is the root, and assurance is the flower. Doubtless you can never have the flower without the root; but it is no less certain you may have the root and not the flower.
Faith is that poor trembling woman who came behind Jesus in the press and touched the hem of His garment (Mark 5:25).
Assurance is Stephen standing calmly in the midst of his murderers and saying, “I see the heavens opened, and the Son of man standing on the right hand of God” (Acts 7:56).
Faith is the penitent thief, crying, “Lord, remember me” (Luke 23:42).
Assurance is Job, sitting in the dust, covered with sores, and saying, “I know that my Redeemer liveth” (Job 19:25). “Though He slay me, yet will I trust in Him” (Job 13:15).
Faith is Peter’s drowning cry, as he began to sink: “Lord, save me!” (Matt. 14:30.)
Assurance is that same Peter declaring before the council in after times, “This is the stone which was set at nought of you builders, which is become the head of the corner. Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved” (Acts 4:11, 12).
Faith is the anxious, trembling voice: “Lord, I believe: help Thou mine unbelief” (Mark 9:24).
Assurance is the confident challenge: “Who shall lay anything to the charge of God’s elect? Who is he that condemneth?” (Rom. 8:33, 34).
Faith is Saul praying in the house of Judas at Damascus, sorrowful, blind and alone (Acts 9:11).
Assurance is Paul, the aged prisoner, looking calmly into the grave, and saying, “I know whom I have believed. There is a crown laid up for me” (2 Tim. 1:12; 4:8).