Mourning is associated with darkness, death and loss. People can experience the loss of a loved person or the loss of health and they cannot be comforted. Struggles and battles will follow. So what does this verse mean?
Where sin is involved, it leads to death. When we sin, we take God out of His rightful place, we replace Him with ourselves as being more important than Him. We question His authority. We are designed to be God’s friends and to have fellowship with Him but sin separates us from God.
This verse refers to us being mournful for our sin and the separation it causes between us and God. It doesn’t mean just being mournful for the consequences it causes us. Sin is as a result of a heart problem. This verse means that God will comfort us if we come humbly before Him and ask Him for mercy through the cross of Jesus Christ.