North Korean leader Kim Jong Un told propaganda officials this week to prioritize loyalty to the ruling party over personal happiness and ensure the people are “sincere” believers in party teachings, according to state media on Tuesday.

Kim did not attend the opening day of the First Short Course of Party Propaganda Officials on Monday, the Rodong Sinmun reported, but sent a letter titled, “On Smashing Formalism and Making a Fundamental Change in the Party’s Ideological Work.”

“Formalism” is a common term used in DPRK state media to refer to an attitude where people who do not sincerely believe