hacer : to make (mi madre hizo la comida my mother made the meal). to do (sus amigos harán lo que puedan his friends will do what they can). to form, make (no hagas un juicio ligero do not make a hasty judgment)...

barro : mud . clay . earthenware vessel . blackhead . blunder, error .

mentir : to lie, tell lies . to deceive, mislead,(las apariencias mienten appearances are deceiving, to belie, contradict .to belie, contradict .

sentir : to feel (siento el calor del sol en la cara I feel the heat of the sun on my face). to experience, feel (sentir alegría to experience joy). to hear (sentí pasos I heard footsteps). to regret,...

knew how to lie in the mud (sabía hacer mentir al barro)

knew how to feel the mud (sabía hacer sentir al barro)

I'm not sure: it's either "he knew how to lie to the clay," or "he knew how to make the clay lie."

(Lie as in to tell fibs!)