Whisk together olive oil, lemon juice, lemon zest, garlic, oregano, thyme, salt, and pepper in a non-reactive bowl until emulsified.
Place chicken breasts in a vacuum-sealable bag or glass dish and coat thoroughly with the marinade.
Refrigerate and marinate for a minimum of 30 minutes, not exceeding 4 hours to prevent tissue breakdown from the acid.
Preheat gas or charcoal grill to medium-high heat, approximately 400 degrees Fahrenheit, and oil the grates using a high-smoke-point oil.
Extract chicken from the marinade and place on the grill grates.
Grill for 5 to 6 minutes per side, maintaining a consistent heat level.
Monitor internal temperature using a digital probe thermometer until it reaches exactly 165 degrees Fahrenheit.
Remove chicken from the heat source and allow to rest on a room-temperature surface for 5 minutes to allow for carry-over cooking and juice redistribution.