Preheat barbecue to medium high or oven to 400 degrees.
Using a basting brush, brush the halibut fillets with olive oil. Then spread garlic and thyme leaves on top of fillets.
Squeeze fresh lemon juice over fillets, and sprinkle with salt.
Place directly on grill or on a baking sheet and into oven. Cook for 10-15 minutes, depending on thickness of fish. Halibut is ready when fish starts to flake.
Remove from grill or oven and cover tightly with aluminum foil for 5 minutes. Serve after 5 minutes of sitting covered with foil.