During his time in Madrid, he was taken in by Doña Justa Jugo Vidal and met with other Filipinos to discuss the Philippine situation. He also met Señorita Maria Angeles Lopez Montero and married her on Christmas Eve in 1898. He published "La Religion del Katipunan", which he wrote during his stay in Montjuïc, and he was commissioned by the British and Foreign Bible Society to translate the Bible to Iloko. de los Reyes later said that this work was "one way by which could contribute to the liberalization of dogmatic religion."