Matsya Purana 187.14

187.14

atha kena prakāreṇa hantavyaṃ tripuraṃ mayā.
paraṃ saṃcintya bhagavān nāradaṃ cāsmarattadā.
smaraṇādeva! saṃprāpto nāradaḥ samupasthitaḥ .. 187.13

He said to himself "How shall I kill the demon?" He then thought of the sage Nârada who appeared then and there, and said "Mahâdeva! what are your behests? Why have you summoned me? I shall carry out your commands"-13 14