The very inadequacy of the Old Covenant mediation was designed to make men see the need for a mediatorial ministry of greater efficacy. To have a broken-down old car to drive is much better than nothing, and one may be thankful for it, yet the frustrations of driving it make you long for a good one; and similarly, the experiences of living under the Old Covenant could not but arouse longings for something better – a better covenant, founded on better promises, holding out a better hope, and resting on the efficacy of better sacrifices. (J.I. Packer, 18 Words)
The word ‘grace’ thus comes to express the thought of God acting in spontaneous goodness to save sinners: God loving the unlovely, making covenant with them, pardoning their sins, accepting their persons, revealing Himself to them, moving them to response, leading the ultimately into full knowledge and enjoyment of Himself, and overcoming all obstacles to the fulfilment of this purpose that at each stage arise. Grace is election-love plus covenant-love, a free choice issuing in a sovereign work. Grace saves from sin and all evil; grace brings ungodly men to true happiness in the knowledge of their Maker. This is the concept of grace with which the New Testament writers work.
(Packer, J.I. 18 Words, Christian Focus Pub., Pg 94).