Salvation we have received comes by grace of God, not by any portion of our deeds. Therefore, we should live thankfully for His grance and devote our life to Him unconditioanlly.
The following verses are biblical teaching on the grace of God, letting us try to understand His unsearchable richness of grace.
"But now for a brief moment grace has been shown from the LORD our God, to leave us an escaped remnant and to give us a peg in His holy place, that our God may enlighten our eyes and grant us a little reviving in our bondage.
'What are you, O great mountain? Before Zerubbabel you will become a plain; and he will bring forth the top stone with shouts of "Grace, grace to it!"'"
"I will pour out on the house of David and on the inhabitants of Jerusalem, the Spirit of grace and of supplication, so that they will look on Me whom they have pierced; and they will mourn for Him, as one mourns for an only son, and they will weep bitterly over Him like the bitter weeping over a firstborn.
[ The Word Made Flesh ] And the Word became flesh, and dwelt among us, and we saw His glory, glory as of the only begotten from the Father, full of grace and truth.
Now when the meeting of the synagogue had broken up, many of the Jews and of the God-fearing proselytes followed Paul and Barnabas, who, speaking to them, were urging them to continue in the grace of God.
Therefore they spent a long time there speaking boldly with reliance upon the Lord, who was testifying to the word of His grace, granting that signs and wonders be done by their hands.