Thanks to his knowledge of the Greek language, he was on good terms with the Greek bishops in Serbia, and thanks to his knowledge of Turkish, he learned that the execution of Karađorđe was planned in the Slaughter of the Knezes. He informed Karađorđe about it in time and thus saved his life.He kept in constant contact with Karađorđe and encouraged him to organize an Uprising. The first insurgents gathered at the wedding of Stevan Tomić in Orašac, at the end of 1803. On that occasion, Father Atanasija swore to the conspirators in the Marićevića jaruga that he would not reveal the secret of his agreement: "Brothers, it has been so many hundreds of years since all our glory was buried in the grave in Kosovo. The holy altars of God, which adorned Serbia as flowers for our emperors and kings, are today stables for Turkish horses. The image of our wives, sisters and daughters is trampled underfoot as if we were all real slaves. But, brethren, in the name of the Creator of God and our Saviour, let us rise up in arms! God will help us, and the tsar (Sultan) will approve it because these Dahije is also working against him!" When the Uprising began, Atanasije swore the people's leaders to mutual harmony and loyalty to Karađorđe. Although old, Atanasija took part in the first battle confronting the Turks in Drlupa. One group of insurgents was commanded by Karađorđe, the other by Priest Atanasije. Just before the battle, Father Atanasije addressed the insurgents as follows: "Brothers here comes the fight with the Turks. Do not, brothers, withdraw or be afraid. God is with us, so who else should we be afraid of? You swear to strike in unison and not to betray." The people replied, "Let us swear!"