Which literary term but I remember now am in this earthly world where to do harm is often laudable good sometime?

The literary term you're referring to is "oxymoron." An oxymoron is a figure of speech that juxtaposes two seemingly contradictory terms. In the example you gave, "to do harm is often laudable good sometime," the terms "harm" and "laudable good" are contradictory because harm is typically seen as something negative, while laudable good is something positive. However, the oxymoron suggests that in certain situations, doing harm can be seen as a good thing.