Ragdoll Cat Is Over Affectionate

My ragdoll loves to sit on my chest when I am laying on my back, hold a piece of my shirt in his mouth and knead my stomach with his front paws. Can you tell me what this means?

I think your cat is demonstrating the greatest compliment you could have. He is enjoying the warmth that you supply him with and bonding with you by savoring the taste of your shirt. The kneading of his paws is just a manifestation of him being content, quite like how humans will wiggle their feet in bed.