He gave Leonardo the job of painting one of the angels holding Jesus ' robe on the left side of the picture . Vasari said that Leonardo painted the angel so beautifully that Verrocchio put down his brush and never painted again . According to Vasari , Leonardo collaborated with Verrocchio on his Baptism of Christ , painting the young angel holding Jesus 's robe in a manner that was so far superior to his master 's that Verrocchio put down his brush and never painted again .