In plain words
Then, so as to spread its inner meaning widely through the world, the maharṣis went on practising tapas. The second they recognised in these words, ‘Vedāham etam puruṣam mahāntam ādityavarṇam tamasaḥ parastāt.’: we have seen the radiant Paramātma who stands beyond the gloom of darkness. People! You too, see Him and be saved. Delight in Him. Choose Him. So they went on teaching. That radiant one is free of self-interest. That one full of radiance is auspiciousness in form. That radiant one is without guṇas. That is why they came to give Him a new name. They called Him Śivaḥ. Śivaḥ means one who is free of the three guṇas. That is, one who does not have the three guṇas. He is the one free of the three guṇas. Because He has no guṇas, He is pure. The guṇas themselves bring impurity. So God has no guṇas, and that is why He is pure. Without guṇas, stainless, ever new. He is the abode. Describing such a principle, they gave Śiva a name and came to call Him Śivaḥ.
He has no guṇas, but all powers are in Him. He is pure, yet He pervades everything. He is the embodiment of all aiśvarya. He is the embodiment of the six aiśvaryas. Aiśvarya, Dharma, fame, renunciation, Jñāna and glory: knowing by experience that these six kinds of riches are with Him, they came to give Him a second name. That name is ‘Īśvaraḥ’. Īśvaraḥ means the embodiment of every aiśvarya. Jñāna is an aiśvarya. Sight is an aiśvarya. Our feelings are an aiśvarya. Conduct is an aiśvarya. Life is an aiśvarya. All of them are aiśvaryas. Even the span of life is an aiśvarya. The ṛṣis of that time showed that not only wealth, gold, goods and vehicles, but also the divine qualities in humanity, are an aiśvarya.
Their researches did not stop there. They came to believe too that He protects those who worship Him, trust Him, sing to Him, adore Him and take refuge in Him. Because it is His nature to enfold those who take refuge in Him, they called Him Śaṅkaraḥ.
For His resolves or His grace there need be no causes whatever. His resolve itself is His cause. The feelings He resolves upon are the forms of all creation. That is why, since He is free in His own resolves, they gave Him another name as well. They called Him ‘Svayambhuḥ’. Because He takes on a body by His own resolve, they named Him Svayambhuḥ.