What does it mean to sit through jail?

This is an allusion. From He Jingping: Willing to sit through the bottom of the prison.

"Sit through the bottom of the prison" is a modern poem. This popular and immortal poem was written by the revolutionary martyr He Jingping in Zhazidong of the Kuomintang's Sino-US Cooperation Institute in the summer of 1948. Written in a concentration camp. For more than half a century, it has been deeply imprinted in people's hearts. In the poem, the author expresses the heroic ambitions of the revolutionary martyrs and his determination to fight the enemy to the end. The poems are permeated with a single-minded revolutionary spirit, deeply shocking readers and touching generations of people. They looked out of the reinforced concrete windows, but they were mentally satisfied because they did not give up hope and resolutely fought against the world and reactionary forces.

Introduction to the background of the poem

"Sit Through the Prison", this popular and immortal poem, was written by the revolutionary martyr He Jingping in Zhazidong Prison in the summer of 1948.

On April 5, 1948, due to betrayal by traitors, He Jingping and Liu Dehui were arrested by the special agents and imprisoned in Zhazidong Prison.

On the first day of the first lunar month in 1949, he, Liu Zhenmei, He Xuesong and other 20 comrades established the "Iron Window Poetry Society" in prison, using fighting poems to fight against the enemy. In the autumn of the same year, the People's Liberation Army was victorious and advancing into the southwest. In order to boost the fighting spirit of his fellow prisoners, he wrote "Sit Through the Prison" full of revolutionary passion. The poem is majestic, passionate, full of lofty ideals and strong revolutionary will. It was composed by fellow inmate Zhou Zongxie and sung in prison. It effectively inspired the fellow inmates to fight unyieldingly in the increasingly cruel prison struggle.