Esp. Una mano lava la otraIt. Una mano lava l'altraIng. One good turn deserves anotherIng. Scratch my beech, and I will claw your elbowUna mano lava la otra. One good turn deserves another. But this phrase is more commonly applied where two persons bespatter each other with fulsome and undeserved compliments. Scratch my beech, and I will claw your elbow.
Fuente: Erasmo, 33.