After living in Halse og Harkmark for some years, he returned to Holum following his father's death in 1849.

[2] In parliamentary politics, Jaabæk eventually emerged as the leader of the oppositional alliance of farmers.

[6] Jaabæk never became one of the leading figures of the new party, but he remained a supporter of Sverdrup for the remainder of his political career.

[2] Due to his rationalistic approach to Christianity, as well as his view of positions in the church as ordinary professions, he became at odds with the Norwegian clergy in the 1870s.

[3] Jaabæk supported many democratic reforms, and spoke up for universal suffrage and equal marriage rights for men and women.