This is only a guess. The first part, "touched by life" means that life's experiences have affected him and molded him into what he is today. The second part is a bit more difficult. Etching can be physically scratching a design or message on to hard objects, such as glass or steel. This requires a hard instrument and often involves the use of acid. In a metaphorical use, etching can refer to imprinting something like an image in one's mind. Another meaning of "etching" is "to delineate", "to define", "to describe in detail". Fire is probably also used metaphorically here. This may refer to trials, tough times, etc., or the heat that is used to strengthen steel or glass. The last part, then, might mean that he has been strengthened by his experience or at least changed (imprinted) by them.