This Wall of Life is located in Southern Elsweyr in Black Heights. There is a quest line that goes with this wall. A father leaves his sick son and goes to the dark side in death. His son falls ill and his father is haunting him to come to him.
There is a small dungeon in which you enter and must kill some of the spirits that have not crossed over. In the end, you see the ghost of the father and the son rushes to him asking him to please stop. Father exchanges some loving words for his son and leaves. The son paints the wall as the corruption is ended and then passes away.