shamayasi tamaH prajaanaaM shaastramayena sthira pradIpena..18
The key words here are: “Sridhara KaruNE! SaasthramayEna sTira pradheepEna prajAnAm tama: Samayasi” (You light the steady lamp of Bhagavath Saasthrams to banish the darkness of ajn~Anam in the minds of the chEthanams). You light this lamp with great affection (samAhitha snEhaa) and with the right kind of wick (anuguNa dasaa arpithEna pradheepEna)
One lights the lamp after adding the oil and placing the wick. That helps one find the way in the surrounding darkness and permits people to get to their destinations. Oh Mother Dayaa Devi! All the chEthanams are Your children. You light a lamp for their benefit. The affection that You have for them is the oil for that lamp. The auspicious guNams that arise at appropriate times are the wicks for that eternal lamp of the Bhagavath Saasthrams and the Vedams. The ajn~Anam of the Jeevans is removed by the lustre linked to the lamp and they travel on the paths laid out by the Saasthrams. Swamy Desikan implies that the provision of Bahgavath Saasthrams as the guiding lamp is an act of Dayaa DEvi.