Hanging up a picture of a woman when she was single

Q: Is it permissible to hang in my house a picture of my wife without her hair covered from when she was single?
A: Yes, since she was not obligated to cover her hair at that time and the picture is modest. If a man begins to have impure thought on account of the picture, that is his problem. But I do not know why you need a picture of your wife hanging in your house. After all, you have your wife there. There is a story of a man who comes to a restaurant and asks: where is the kosher certification document? The owner says: we don't have a document but don't you see the pictures of the famous Rabbis hanging on the wall? There is a picture of the Ben Ish Chai and a picture of Ha-Rav Ovadiah Yosef. The man responds: If they were in the kitchen and your picture was hanging on the wall, I would eat, but since you are in the kitchen and they are hanging on the wall, I am not eating.