For painting he studied under Laurynas Gucevičius and Franciszek Smuglewicz, architecture with Michała Szulca and sculpture with Andrzej Le Brun.

From 1811 to 1826, Jelski worked as a professor of the University of Vilnius, where he trained many renowned sculptors.

At the end of his life he was forced to arrange English kitchens and build steam mills in the estates.

He performed primarily classical sculptures and bas-reliefs and religious monuments and busts and medallions which displayed portraits of famous people of Polish culture and historical figures.

[1] Some of his key works include the figures of plaster in the Vilnius Cathedral, statues and bas-reliefs at the Evangelical Reformed Church, four sculptures at St. Peter and St. Paul's Church, and numerous monuments in Vilnius and Trakai.