Grace is best described as undeserved kindness.  God’s gift of forgiveness comes completely from His love and mercy; we can’t earn it and don’t deserve it in any way.  

The meaning of the Greek word translated “grace” emphasizes this. Charis means “a favor done without expectation of return; the absolutely free expression of the loving kindness of God to men finding its only motive in the bounty and benevolence of the Giver; unearned and unmerited favor” (Spiros Zodhiates, The Complete Word Study Dictionary, New Testament).

Mercy is an act of kindness or favor offered by not enforcing a penalty or punishment a person or community have earned or they deserve due to their personal acts of moral or legal trangressions or behaviors.

Jesus' name literally means "Salvation".  Salvation comes through Jesus Christ alone.  

Neither is there salvation in any other: for there is none other name under heaven given among men, whereby we must be saved. [Acts 4:12 KJV]

Salvation involves the rescue, redemption, and restoration of a dead spirit and a dying body attached to a doomed sinner's soul. 

The just penalty for all sins is death, and therefore : 

• No Person Can Earn Their Salvation By Being Good. 

• No Person Can Earn Their Salvation By Being Religious.

Salvation is God’s way of redeeming people for Himself by dispensing mercy, grace but also justice at the same time, by taking upon Himself punishment that we deserved through Jesus on the cross.