astausid dharim ekagra-
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Prahlada Maharaja fixed his mind and sight upon Lord Nrsimhadeva with full attention in complete trance. With a fixed mind, he began to offer prayers in love with a faltering voice.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The word susamahitah means “very attentive” or “fully fixed.” The ability to fix the mind in this way is a result of yoga-siddhi, mystic perfection. As it is stated in Srimad-Bhagavatam (12.13.1), dhyanavasthita-tad-gatena manasa pasyanti yam yoginah. One attains yogic perfection when he is freed from all material diversions and his mind is fixed upon the lotus feet of the Lord. This is called samadhi or trance. Prahlada Maharaja attained that stage beyond the senses. Because he was engaged in service, he felt transcendentally situated, and naturally his mind and attention became saturated in transcendence. In that condition, he began to offer his prayers as follows.