In 1531 Rej moved to Kobyle, in the Chełm area, which had been bequeathed to his wife, and thereafter, he frequented the court of Hetman Mikołaj Sieniawski.

Living during the Golden Liberty embraced by the Polish nobility, tolerance characterized his oversight and this philosophy was carried on by his sons.

[4][5] In 1543 Rej debuted as a writer, under the pen name "Ambroży Korczbok Rożek," with his most famous book, A Brief Discussion among Three Persons: a Lord, a Commune Chief, and a Priest (Krotka rozprawa między trzemi osobami, panem, woytem a plebanem).

He authored prose works that described the ideal of the Polish nobleman, criticized the Catholic Church, and showed a genuine solicitude for his country.

His poetic meter discloses a deliberate effort to impart to the medieval metrical model with which he was so familiar, a regularity that it lacked.