Ordained as a priest at a relatively young age, Lazarević was described as a lively, gun-wearing horseman who joined the Serbian rebels in their fight against the renegade Janissaries (Dahije) to avenge his cousin.

He quickly showed prowess and by the time the uprising against the Ottomans had begun he was chosen as the commander of a unit in western Serbia.

After his return home and marriage, he was ordained a priest by bishop Danilo of Valjevo in 1796[1] and was given the care of the villages of Ljutice and Koceljeva.

[3] Lazarević's paternal cousin Ranko, the son of Lazar,[1] was a knez (Christian village chief) in the Tamnava area.

Serbs that supported the Empire were harassed by the Janissaries; Bego Novljanin and Ćurt-oglija who sat at Šabac killed Ranko at the beginning of 1800.

17 January] 1806 with Živko Dabić, Lazarević's unit defeated the Turks at Ranitovac after a day of fighting, with much of enemy troops drowning in the Jadar river.

[1] He was nearly killed at the Battle of Mišar (August 1806), but was instrumental in the victory; Karađorđe ordered Lazarević to hide in the woods with cavalry, and on the sound of his cannon, charge into the rear of the Ottoman troops.

He also fought on the other side of the Drina, at Glavice above Bijeljina (where Meho Orugdžić fell), between Zvornik and Srebrenica, and destroyed Ottoman troops crossing towards Sarajevo.

[8] The epic poet and guslar Filip Višnjić (1767–1834) enumerated Lazarević's most famed battles as Loznica (October 1810), where he wrested the control of the town from the Ottomans, and Novo Selo on Krstovdan, where he killed Pejzo Mehmed-Aga.

The Austrians escorted him to Judenburg in Styria, from where he then left for the Russian Empire, where he stayed until 1832 when he returned to what had become the Principality of Serbia after the Second Serbian Uprising (1815–17), ruled by Miloš Obrenović (a fellow revolutionary commander, who had ordered for the assassination of Karađorđe).

[9] Lazarević was dark-haired, rawboned, nimble, of few words; lively, energetic, orderly, sharp; just towards the young and listening to the elderly.