The bow and the arrows in the forehands has also another significance. What we have to surrender to Her feet, namely our mind and the senses, She draws by Her own initiative to Herself; the bow draws the mind and the arrows the senses, to Herself. It is as if a loving mother says to her child: ‘Dear child, why do you have to fall at my feet; I will take you onto my lap’!
This whole shloka is a fit one for meditation. It reminds us that the bow and arrows that turned the Ishwara Himself - the Supreme who is nothing but a bundle of Knowledge, cit - into a creation-mode through the artifice of making Him fall in love with Ishwari, who thereby became Shiva-kAma-sundari; that same bow and arrows now draw the medley of minds and senses of the jIvas and keep them under its control, thus protecting them (spiritually).
In fact the bottom line is that even this action of ‘drawing’ and ‘protecting’ is not done by the bow and arrows but by just Her feet.