Make marinade: In an electric coffee/spice grinder finely grind cumin seeds and cloves.
In a blender blend ground spices with remaining marinade ingredients until smooth.
Cut chicken breasts crosswise into 1/4-inch-thick strips and in a large sealable plastic bag combine with marinade.
Seal bag, pressing out excess air and turn bag several times to coat chicken well.
Marinate chicken at least 1 day and up to 2.
While chicken is marinating, soak skewers in water at least 1 hour.
Prepare grill (or preheat oven to its highest temperature, 500 degrees to 550 degrees).
Remove skewers from water and pat dry.
Thread 1 piece chicken lengthwise onto each skewer and grill on an oiled rack set 5 to 6 inches over glowing coals, turning over once, until just cooked through about 5 minutes.
(Alternatively, in a lightly oiled shallow roasting pan arrange skewers in one layer and roast in middle of oven.)