Murugan in tamil means beautiful. Even amomg human beings, one who is more compassionate and peaceful has a more serene face than the others. So God who is a personification of all compassion and peace and knowledge is the most beautiful form and ancient saints who realiszd the form of God by their penance, wrote it down in scriptures and also inculcated them to sculptors and painters and that is what we see even today in sculptures and paintings in Indian temples.
Subrahmanya is worshipped for all boons especially that of good children. He is an inspiration to many saints who praise him as Guru, a master who blesses the higher intellect to understand esoteric knowledge of inner life to reach Godliness.
One such saint was Arunagirinathar. Arunagirinathar becomes vexed of his lowly life of seeking pleasure and jumps off a Gopuram to kill himself. Murugan himself saves Arunagirinathar by holding him in his hands and initiates him into a saintly life. After years of penance he becomes a yogi and goes on pilgrimage all over India singing the glory of Murugan in various temples. Those songs called Thiruppugazh (The praise of God) are so moving thateven a stone hearted person will become an ardent devotee of Murugan on a cursory reading of them. One can see the grace of God in such works which were written just out of compassion towards us who don't have any taste of the true pleasure that comes out of pure life and selfless devotion.