His son disapproved at first, because Ilija's work was not as precise or refined as the official Hlebene School's Reverse painting on glass techniques.

[1] Much of his work dealt with religion and folk legends and two-headed and two-faced creatures are a common theme.

Unlike the traditional peasant style of his region, Bosilj created a flat two-dimensional world often inhabited by men and demons, snakes, fish, anthropomorphic creatures, and spacemen.

In the Iliad Cycle, which has nothing in common with the famous Homerian epic but is related to the painter’s name, there are frequent artistic allusions to the real world and fights against human foolishness, duplicity, and hypocrisy.

The mere names of his paintings, like in Sekulić and Jakić, help us to get acquainted with his world full of personal symbolism.

He created in anti-illusionist and abstract manner, eliminated reminiscences and generalized due to his purely authentic understanding of the realistic.

Ilija’s dynamic treatment of the colored structure points to outstandingly modern dimension of his pictorial expression.

The backgrounds in his paintings are often empty and flat, while rhythmically sequenced figures are floating, animated with wavy lines.