one who mercifully had his yŏga nidhrā —

your sleeping —

he grew up mercifully —

growing (without any fear) —

grew (to have his enemies destroyed and to sustain himself with the materials which are dear to his devotees) —

ās said in mul̤aiththa seeṝam viṇ sudap pŏy [periya thirumozhi – 1.7.7] (m̐with anger that scorched those in the sky (dhevas)), even the devotees like dhĕvas too were scared and anguished, ḥe started growing very quickly, —

 one who mercifully grew —

 mercifully resting there —

has grown? —

 one who grew in his divine form —