It appears that the great sage Atri Muni had no specific idea of the Supreme Personality of Godhead. Of course, he must have been conversant with the Vedic information that there is a Supreme Personality of Godhead who is the creator of the universe, from whom everything emanated, who maintains this created manifestation, and in whom the entire manifestation is conserved after dissolution. Yato va imani bhutani (Taittiriya Upanisad 3.1.1). The Vedic mantras give us information of the Supreme Personality of Godhead, so Atri Muni concentrated his mind upon that Supreme Personality of Godhead, even without knowing His name, just to beg from Him a child exactly on His level. This kind of devotional service, in which knowledge of Gods name is lacking, is also described in Bhagavad-gita where the Lord says that four kinds of men with backgrounds of pious activities come to Him asking for what they need. Atri Muni wanted a son exactly like the Lord, and therefore he is not supposed to have been a pure devotee, because he had a desire to be fulfilled, and that desire was material. Although he wanted a son exactly like the Supreme Personality of Godhead, this desire was material because he did not want the Personality of Godhead Himself, but only a child exactly like Him. If he had desired the Supreme Personality of Godhead as his child, he would have been completely free of material desires because he would have wanted the Supreme Absolute Truth, but because he wanted a similar child, his desire was material. Thus Atri Muni cannot be counted among the pure devotees.