This question, "what is grace" plagued me more into knowing the answer and being sure beyond a shadow of a doubt.

In the beginning of time, It was God's intention to be in fellowship with His people. We all know that sin took us right out of that equation. But, since God is always way ahead of Satan, He already had a plan set in motion to bring us back to Himself, all was not lost.

He told Satan that the seed of the woman would crush his head. That seed was Christ who would be sent to redeem God's children and set them free grace from captivity to sin. Through Christ's sinless life, death and resurrection, He alone healed all our diseases and freed us from Satan's trap of death. This is the doctrine of Atonement.

Christ came to earth as God in a manly form to show us the way to become grace "at one" with Him. This atonement increases our desire to enter into God's Kingdom with righteousness and virtue. This "at one" experience is God's free gift of grace. Yes, it is undeserved, it's unmerited but He gave us His all in order to humble us and give Him all our praise.

God gives this free gift of grace to those who are truly repentent of their sins. Not everyone will take it. This is not a gift for the faint of heart. God is just and holy and therefore He will not wince at our sins, He will punish those who do not accept this gift.

We can either pay for our own sins, but that would take forever and then some as we would spend our eternity in hell. It is a serious crime against God. Or...we can let someone else pay the price for our sins. We all have them and Jesus is the One Who paid that price already.

"For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish, but have eternal life." John 3:16

This is the ultimate gift of unconditional love that God so freely gives us. It's ours for the taking when we truly confess Jesus with our mouth and mean it with our whole heart.

Upon this confession, God then makes new creatures out of us. His grace isn't ever having to go through life on our own. Even though things seem overwhelming, His grace is sufficient to carry us through the tests so that they may become our testimonies in giving Him all the glory.

Salvation is not to be presumed however. It's not just doing good works. Being a good person who has no faith will not earn you a place in God's Kingdom. Only true faith through His gift of grace will get you there.

"For by grace you have been saved through faith; and that not of yourselves, it is the gift of God; not as a result of works, that no one should boast. For we are His workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them." Ephes. 2:8-10

In the end times, people will listen to false doctrine and they will ask "Where is God?" But know this, He is in you, He will never leave you nor forsake you.

"You therefore, beloved, knowing this beforehand, be on your guard lest, being carried away be the error of unprincipled men, you fall from your own steadfastness, but grow in the grace and knowledge of our Lord and Savior Jesus Christ. To Him be the glory, both now and to the day of eternity. Amen" 2 Peter 3:18-19

We will have to face God on judgement day, first those of us who are saved through grace. We will have to answer for the deeds we did while here on earth and then those who remain unrepentant will have to answer to Him at the Great White Throne of Judgement before He casts them into the lake of fire forever.
Just as He did in the days of Noah, those who weren't prepared were destroyed in the flood. The second time around He says He will destroy us with fire. This is something I don't care to test Him on.