Parahiṁsā u dayā (Violence and Mercy) was first published in Sajjana Toṣaṇī Vol.9, issue 9 in 1897. In this essay, Bhaktivinoda Ṭhākura describes the necessity of compassion and the different types of mercy for a jīva.
Jīvera Dayā (Mercy to the Living Entities) was published in Sajjana Toṣaṇī, Vol. 4. Issue 8 in 1893. In this important article, Śrīla Bhaktivinoda Ṭhākura explains the absolute necessity for a Vaiṣṇava to cultivate compassion for other living beings and states that this is one of the most important qualities of a devotee.