Ruben's The Martyrdom of Saint Thomas depicts the apostle the moment he is struck by a spear, causing his death.

Dressed in black and barefoot, Thomas clutches a stone cross[2] while reaching towards an angel handing him a palm frond.

It is thought that Rubens used the story of Saint Thomas from the Legenda Aurea, or Golden Legend by Jacobus de Voragine.

[2] According to Pedro de Ribadeneyra's Flos Sanctorum, Saint Thomas wore an old cloak and dressed like a poor man.

[1][3] Uncommon to the time in which Thomas lived, he was depicted barefoot with unusual dress for an Apostle, wearing a cowl similar to the ones worn by mendicant friars.

[1] To make Thomas appear as a member of the Augustinian order in Prague, Rubens decided to dress the Apostle similarly, with bare feet.

[1] The purpose of doing so was to generate feelings in the Augustinian observers to view Saint Thomas as a model and serve their faith better because his martyrdom.

Rubens painted twisted columns, a highly symbolic value in Christian art, but paired it with a pagan idol and elephant heads.

[2] Rubens references Pedro de Ribadeneyra's Flos Sanctorum again, in which there is a story of Saint Thomas moving a large tree singlehandedly when several elephants could not.

[2] For the idol at the top of the column, Rubens referenced Imagini delli dei de gl'antichi, a sixteenth century book detailing the images of the gods of antiquity.

[2] The purpose of presenting the idol this was to relay the message that anything against the Christian religion is work of the devil, conveyed through the devil-like figure.