speak from experience

speak from experience

To talk (about something) having had prior experience and thus a more credible or worthwhile viewpoint. I'm speaking from experience when I tell you that a robust investment portfolio is absolutely critical to achieve the kind of pension you desire. A: "Sarah said to have a lawyer look over the contract to make sure it's all above board." B: "Well, I know she speaks from experience, so I would listen to her."
See also: experience, speak