Rinse the red split lentils under cold water until the water runs clear.
In a small saucepan, combine the lentils, vegetable broth, and minced garlic clove.
Bring to a boil, then reduce heat to low, cover, and simmer for 8 to 10 minutes until the lentils are tender and have absorbed most of the liquid.
Remove from heat and stir in the ground cumin, sea salt, black pepper, and half of the lemon juice; let cool slightly.
In a small bowl, whisk together the Greek yogurt and the remaining lemon juice until smooth.
Dice the cucumber and red onion, and finely chop the fresh parsley.
Warm the whole wheat tortilla in a dry skillet for 30 seconds per side until pliable.
Spread the savory lentil mixture down the center of the tortilla, then top with the diced cucumber, red onion, and fresh parsley.
Drizzle the creamy yogurt sauce over the vegetables and sprinkle with crumbled feta cheese.
Fold the sides of the tortilla inward and roll tightly to serve.