Place the chicken in a gallon sized ziptop bag. Add in the oil, lemon juice, oregano, parsley, basil, garlic powder, onion powder, salt, and pepper. Let out most of the air from the bag and zip it closed. Massage the bag to make sure all the ingredients get mixed and the chicken is completely coated. Set the bag on the counter for 30 minutes to 2 hours. Use this time to prepare the toppings.
Heat a medium to large skillet over medium high heat. Add the marinated chicken a handful at a time to avoid lowering the temperature of the skillet too much. Since the chicken is already marinating in oil, there is no need to add any to the skillet.
Cook until the meat is thoroughly cooked, about 5-8 minutes.
Heat up the grill - gas grill set to medium; charcoal grill - place the coals in a pile near the back.
Slide several pieces of chicken on each skewer. Place them on the grill. Charcoal grill place them toward the front of the grill to prevent flare-ups.
Close the grill lid and cook for 5 minutes. Keep turning the skewers and cooking in 3-5 minute intervals with the lid closed until the chicken is thoroughly cooked. I find it takes 10-15 minutes on my both my gas and charcoal grill.
When the chicken is cooked, remove the skewers from the grill. Carefully remove the chicken pieces from the skewers.
Warm up the pitas on the stove, grill, or microwave.
Place some chicken on the pita and top with your favorite toppings!