The grace is something that began way back in the Old Testament when Noah found grace in the eyes of the lord. This is the first time grace is mentioned in the bible (Genesis 6:8). The grace in the Old Testament here just meant favour so Noah found favour in the eyes of the lord.
Now many Christians have been taken up by too much religion and they think that grace is something that people have just come up with. Religion looks at getting favour through works for example some religions think that righteousness is got through the things that are done by men for example people think being humble is being righteous this is not true because the bible says we are justified by faith (Romans 3:28) . So it’s the same thing we grace we don’t work for it because it’s God who works in us both to do and to will according to his good pleasure.
When you accept the grace of God to work through you it ceases to be your works in more it’s now God who works in you (Romans 11:6)
So when Christ died on the cross we got access to the grace of God, for the bible says in (John 1:17) For the law was given by Moses but grace and truth came by Jesus Christ.
Apostle Paul in the bible gives a more clear view of the grace of God through the different testimonies that he gives for example (1corinthians 15:10) but by the grace of God I am what I am and his grace {which was bestowed} upon me was not in vain; but I laboured more abundantly than they all: yet not I, but the grace of God which was with me.
So Paul is telling us that yes he worked hard but it was the grace of God that was working in him.
So I ask us all as believers to embrace the grace of god and you can only do that by believing and having faith in God. All him to work through you