Grace is free. Under the law it was do good get good and do bad get bad. That’s the way of the law. Obey and you will be blessed. Disobey and you will be cursed.
“But now has He obtained a more excellent ministry, by how much also He is the mediator of a better covenant, which was established upon better promises” (Hebrews 8:6).
That old way was hard. The promises were conditional. But now through Jesus the promises are “are Yes, and in Him Amen,” (Corinthians 1:20 NKJV). Everything is free. Jesus paid for it all. God made it as easy as possible for us. We can’t work for it. We can’t merit it. We don’t deserve it in ourselves. It’s a free gift solely by God’s favor on us. You don’t have to pay for it. All we need do it believe it.
“But not as the offence, so also is the free gift. For if through the offence of one [Adam] many be dead, much more the grace of God, and the gift by grace, which is by one man, Jesus Christ, has abounded to many” (Romans 5:15).