In 1905, de los Reyes once again left for Spain where he stayed until 1909. During this time he worked as a juror in Barcelona until 1908. He also went back to mend relations with his wife, María Ángeles López Montero, who repeatedly urged him to stay away from politics. During his stay in Spain, he wrote texts such as "Gregio Aglipay y otros prelados de la Iglesia Filipina Independiente" (1906) and "Biblia Filipina". He also published "La Religion Antigua de Filipinas" (1909).