Peel husks back, but do not remove. Using a stiff brush or your fingers, remove silk from corn. Pull husks back up around corn. In a large saucepan or container, cover corn (husks on) with cold water. Soak for at least 1 hour. Drain, shaking corn to remove excess water. Cover corn as much as possible with husks. If necessary, tie the tips of the husks together with wet kitchen string.
Grill corn (with husks) on an uncovered grill directly over medium-hot coals about 25 minutes or until tender, turning several times. Carefully remove the husks and strings.
Meanwhile, in a small saucepan combine margarine or butter, lemon juice, and thyme. Heat on the grill or stovetop until margarine is melted. Brush mixture over the corn before serving. Makes 6 side-dish servings.