While I would admit--man could have no righteousness without Christ's work, IE--His Atonement and Resurrection(free gift to all men)---could you collate your claim with the Biblical witness?
1 John 3:7----King James Version
7 Little children, let no man deceive you: he that doeth righteousness is righteous, even as he is righteous.
That was made possible through God's Atonement and Resurrection. Those who walk in His light(doeth righteousness)--are those who God gives His grace to, as His Blood unto the forgiveness of their personal sins. The Atonement and Resurrection absolved all men of death and hell--as it relates to the automatic condemnation which befell all men due to the Fall--and now allows all men to receive of His grace unto life--through meeting the conditions of the Redeemer:
Hebrews 5:9---King James Version
9 And being made perfect, he became the author of eternal salvation unto all them that obey him;
A "covenant" is a two party agreement.