In the second reading St Paul tells us to be the children of light and put away the deeds of darkness, have nothing to do with them. Some people spend a lot of their...many of their years, a lot of their time and energy to hide something. Whether it's because it's painful, whether it's because they feel shame or guilt, or it's the family secret. Lots of time and energy keeping something in the dark.
And there's a slavery with that, because as you have to keep that in the dark, just imagine this big chain tied to the thing and you. But as over the 24 hours of confession, and at any other given time, a few people break free of their chains and they decide that they have had enough, and they need to tell someone, and they come to tell the priest, and they come to tell God. They bring it into the light, in there, finally, after carrying the burden for so long, and when they receive the Lord's forgiveness and grace, they are free. Because the brought it into the light.