The law, whose minister is Moses, was given to bring us into the knowledge of ourselves—that we might thereby feel and perceive who we really are by nature. The law condemns us and all our deeds, and is called by Paul (in 2 Corinthians 3) the ‘ministration of death’. For it kills our consciences and drives us to desperation, inasmuch as it requires of us that which is impossible for our natures to do. It requires of us the deeds of a whole man. It requires perfect love, from the very bottom and ground of the heart, as much in everything we suffer as well as in the things we do. But, says John in the same place, grace and truth is given to us in Christ so that when the law has passed upon us and condemned us to death (which is its nature to do), then in Christ we have grace—that is to say, favor and promises of life, mercy and pardon, freely by the merits of Christ. And in Christ we have verity and truth in that God, for his sake, fulfills all his promises to those who believe. Therefore the Gospel is the ministration of life. Paul calls it, in the afore-mentioned place in 2 Corinthians, the ‘ministration of the Spirit and of righteousness’.
In the gospel, when we believe the promises we receive the spirit of life and are justified, in the blood of Christ, from all things in which the law condemned us. And we receive love for the law, and power to fulfill it, and grow therein daily. Of Christ it is written, in the afore-mentioned John 1, This is he of whose abundance, or fullness, we have all received grace for grace or favor for favor—that is to say, for the favor that God has to his Son Christ, he gives to us his favor and goodwill, and all gifts of his grace, like a father to his sons. Paul affirms this, saying, He loved us in his beloved [that is, in Christ] before the creation of the world. Thus Christ brings the love of God to us, and not our own holy works.
Christ is made Lord over all and is called in scripture God's mercy-stool [or, mercy seat]: therefore whoever flees to Christ can neither hear nor receive from God anything other than mercy.
In the Old Testament are many promises, which are nothing other than the Evangelion, or gospel, to save those who believed them from the vengeance of the law. And in the New Testament there is frequent mention of the law to condemn those who do not believe the promises. Moreover, the law and the gospel may never be considered as if they are separate the one from the other, because the gospel and promises serve only for troubled consciences brought to desperation by the law—which consciences feel the pains of hell and death under the law and are in captivity and bondage to the law. In all my doings I must have the law before me to condemn my imperfectness. For all I do (be I ever so perfect) is yet damnable sin when compared to the law, which requires the ground and bottom of my heart. I must therefore always have the law in my sight so I may be meek in the spirit and give God all the laud and praise, ascribing to him all righteousness and to myself all unrighteousness and sin. I must also have the promises before my eyes so I do not despair—in which promises I see the mercy, favor and good-will of God upon me in the blood of his Son, Christ, who has made satisfaction for my imperfectness and has fulfilled for me that which I could not do myself.A Pathway Into the Holy Scripture
By William Tyndale (c. 1494 – 1536)