There is an order that eventuates in receiving God’s mercy and grace. They are not interchangeable.~ Lisa Blair
God gives us His grace. His mercy is how He provides our request for help. Vine’s Complete Expository Dictionary (pp. 341) puts it this way:
Mercy is the act of God. Grace describes God’s attitude toward the lawbreaker and the rebel; mercy is His attitude toward those who are in distress.
God’s purpose for extending His grace and mercy upon us is to provide a means of salvation. God’s grace must always precede mercy. Only the forgiven can be blessed with God’s mercy.
Mercy is through the everlasting covenant God made with David, particularly pardoning mercy, and mercies that are refreshed everyday. We must approach God boldly without any fear or doubt. Mercy is ours each day. When in prayer, remind God of the covenant and ask for daily mercies. Mercy is like a daily vitamin, your body must be replenished each day, just as your being is through daily mercies.
The commentary from Barnes Notes, BibleHub.com, reads, “we may obtain mercy – this is what comes first. We need pardon – as the first thing when we come to God. We are guilty and self-condemned – our first cry should be for mercy.” Those who understand their need for forgiveness are best prepared to obtain God’s favor.
Finding grace, is finding favor, “strength, help, counsel, direction, support, for the various duties and trials of life. Even when pardoned, we need grace to keep us from sin and to aid us in the day of temptation..”
As Christians, we have the privilege of boldly coming before the throne, “we are sinful and need mercy; we are feeble, and need grace to help us. There is not a day of our lives in which we do not need pardon; not an hour in which we do not need grace.”
Easy way to remember – There is an order that eventuates in receiving God’s mercy and grace. They are not interchangeable.
Mercy is for past sins; grace for future work, trials, and resistance to temptation. (Vincent’s Word Studies, biblehub.com)