In a medium bowl, whisk together the olive oil, lemon juice, garlic, Dijon mustard, honey, oregano, thyme, salt, and black pepper until well combined.
Place the chicken breasts in a large resealable plastic bag or a shallow dish. Pour the marinade over the chicken, ensuring all pieces are well coated. Seal the bag or cover the dish and refrigerate for at least 1 hour, or up to 8 hours for more flavor.
Preheat your grill to medium-high heat.
Remove the chicken from the marinade and discard the marinade.
Grill the chicken for 6-8 minutes per side, or until the internal temperature reaches 165°F and the chicken is cooked through.
Remove the chicken from the grill and let it rest for 5 minutes before slicing.