Grace, we might say, is a response, an application of God’s character and attributes, to human rebellion. Grace is that aspect of divine action by which God blesses his rebellious creatures, whether through preservation (common grace) or salvation (special grace). It characterizes the manner in which he deals with those who through their rejection of him as their Creator and sovereign deserve nothing from him and yet whom he still chooses to bless. In salvation in particular the character of grace is manifest. A loving God, faced with the rebellion of his creatures, desires to bring them back into communion with himself. Yet his holiness cannot simply allow their sin to pass without response, for if God allows our unholy rejection of him to stand, he is contradicting his own holy nature. The answer is grace: action on God’s part, motivated by love and shaped by holiness, which takes account of the seriousness of sin yet brings sinners back into communion with him.
Carl Trueman, Grace Alone