From Holiness by J.C. Ryle (as published in Faithfulness and Holiness: The Witness of J. C. Ryle, p. 144):
Sanctification is always a progressive work. Some men’s graces are in the blade, some in the ear, and some are like full corn in the ear. All must have a beginning. We must never despise “the day of small things.” And sanctification in the very best is an imperfect work. The history of the brightest saints that ever lived will contain many a “but,” and “howbeit,” and “notwithstanding,” before you reach the end. The gold will never be without some dross—the light will never shine without some clouds, until we reach the heavenly Jerusalem. The sun himself has spots on his face. The holiest men have many a blemish and defect when weighted in the balance of the sanctuary. Their life is a continual warfare with sin, the world, and the devil; and sometimes you will see them not overcoming, but overcome. The flesh is ever lusting against the spirit, and the spirit against the flesh, and “in many things they offend all” (Gal. 5:17; James 3:2).
But still, for all this, I am sure that to have such a character as I have faintly drawn [of holiness], is the heart’s desire and prayer of all true Christians. They press towards it, if they do not reach it. They may not attain to it, but they always aim at it. It is what they strive and labour to be, if it is not what they are.