Place coarsely chopped save in a small saucepan with white wine. Bring to a boil over medium heat, stirring and pressing sage to release flavor. Remove from heat. Cover tightly and let steep for 5 minutes.

Strain sage liquid, pressing leaves with the back of a spoon to extract all the liquid. Discard solids and return liquid to saucepan. Add mustard seeds. Cover and let stand at room temperature until seeds have absorbed most of the liquid, about 2 hours.

COMBINE mustard seeds and liquid and vinegar in a grinder, blender or food processor fitted with a metal blade. Process until blended and most seeds are well chopped, but retaining a slightly grainy texture.

TRANSFER mixture to a saucepan and add lemon zest, lemon juice, honey, salt and reserved finely chopped sage. Bring to a boil over high heat, stirring constantly. Reduce heat to low and boil gently, stirring frequently, until volume is reduced by a third, about 20 minutes.

LADLE hot mustard into jar or crock. Let cool before refrigerating. Serve with venison and beef.