To fall from grace doesn't mean to fall out of God's will, favor, fellowship, or a right standing with him because we aren't living right (sin). That is what is traditionally taught in churches. But did you know that is not what is taught in the BIble?
Biblically, to fall from grace means to try to earn God's acceptance, blessings, closeness, and fellowship (a right standing with God) by living right, such as following the Ten Commandments, praying, reading the Bible, having quiet times or devotions, tithing, going to church, fasting, worshiping, attending small groups, serving in a ministry, confessing all your sins, having an accountability partner...the list goes on.
Galatians 5:4 says,
"You are trying to be justified by the law, have alientated yourselves from Christ, you have fallen from grace."
Do you see it?
To fall from grace is to try to be in right standing with God or try to earn his favor, blessings, fellowship, or acceptance through the law (good works, morality, religious, spiritual, or church activity and disciplines).
If we are trying to be right with God, stay in fellowship with or close to God, or earn something from him, then we are no longer trusting in Jesus and what he did for us on the cross, but we are trusting in ourselves.
So to fall from grace is to stop trusting in Jesus, who made us right with God, brings us into fellowship with and close to God, and in whom we are blessed with every spiritual blessing, and to start trusting in our own good works.
Grace is everything God has freely and fully done for us in Christ to bless us and bring us close to himself in a relationship where we are totally loved and accepted.
To try to achieve what God has freely given is to fall from grace.