It’s interesting to note in the Last Supper fresco which Leonardo began to paint in the mid 1490’s, both the right hand of Jesus and the left hand of Judas are shown as claw-shaped. John’s hands are joined as if symbolising the good and evil sat either side of him.
The feminised figure of John is possibly a portrayal of Leonardo’s right hand man, Salaì, who was described by Vasari as “a graceful and beautiful youth with curly hair, in which Leonardo greatly delighted” even though his master also wrote that his servant for 25 years was “a liar and a thief”.
Also very noticeable is the large knot resting on the shoulder of Barholomew standing at the left end of the table. Even in the fresco’s poor state it can be seen to represent a lion’s head to echo the fiery head of Batholomew. The arm band is also significant and symbolic of restriction. Both these motifs are repeated in Mantegna’s Parnassus painting in which he refers to the works of Leonardo.
All the figures in Leonardo’s Last Supper can be interpreted as representing a claw hand or pointing to Leonardo’s shoulder injury.