The sages of Naimiṣāraṇya were practically sufferers from the smoke of a sacrificial fire and were doubtful about the result, but by hearing from a realized person like Sūta Gosvāmī, they were fully satisfied. In the Brahma-vaivarta Purāṇa, Viṣṇu tells Śiva that in the age of Kali, men full of anxieties of various kinds can vainly labor in fruitive activity and philosophical speculations, but when they are engaged in devotional service, the result is sure and certain, and there is no loss of energy. In other words, nothing performed for spiritual realization or for material benefit can be successful without the devotional service to the Lord.
(Srimad Bhagavatam----1:18:12----purport).

Lord Śiva and Lord Brahmā are two chiefs of the demigods. They are full of mystic powers. For example, Lord Śiva drank an ocean of poison of which one drop was sufficient to kill an ordinary living being. Similarly, Brahmā could create many powerful demigods, including Lord Śiva. So they are īśvaras, or lords of the universe. But they are not the supreme powerful. The supreme powerful is Govinda, Lord Kṛṣṇa. He is the Transcendence, and His transcendental attributes cannot be measured even by such powerful īśvaras as Śivaand Brahmā. Therefore Lord Kṛṣṇa is the exclusive shelter of the greatest of all living beings.
(Srimad Bhagavatam----1:18:14----purport).

The living entities are not as powerful as the Lord's plenary expansions, and therefore there are two different types of expansions. Lord Brahmā is generally one of the living entities, and Lord Śiva is the via medium between the Lord and the living entities. In other words, even demigods like Lord Brahmā and Lord Śiva, who are the chief amongst all demigods, are never equal to or greater than Lord Viṣṇu, the Supreme Personality of Godhead. The goddess of fortune, Lakṣmī, and all-powerful demigods like Brahmā and Śiva are engaged in the worship of Viṣṇu or Lord Kṛṣṇa; therefore who can be more powerful than Mukunda (Lord Kṛṣṇa) to be factually called the Supreme Personality of Godhead?
(Srimad Bhagavatam----1:18:21----purport).

The goddess of fortune, Lakṣmījī, Lord Brahmā and Lord Śiva are not independently powerful; they are powerful as expansions of the Supreme Lord, and all of them are engaged in the transcendental loving service of the Lord, and so also are the living entities. There are four sects of worshipful devotees of the Lord, and the chief amongst them are the Brahma-sampradāya, Rudra-sampradāya and Śrī-sampradāya, descending directly from Lord Brahmā, Lord Śiva and the goddess of fortune, Lakṣmī, respectively.
(Srimad Bhagavatam----1:18:21----purport).

By chanting the Lord's holy name, one can derive all the stipulated energy synchronized from all sources. Therefore, one should not equalize the supreme holy name of the Lord with any other name. Brahmā, Śiva or any other powerful god can never be equal to the Supreme Lord Viṣṇu.
(Srimad Bhagavatam----2:1:12----purport).

The effulgent luminary planets like the sun and the moon are situated almost in the midplace of the universe, and as such they are to be known as the chest of the original gigantic form of the Lord. And above the luminary planets, called also the heavenly places of the universal directorate demigods, are the Mahar, Janas and Tapas planetary systems, and, above all, the Satyaloka planetary system, where the chief directors of the modes of material nature reside, namely Viṣṇu, Brahmā and Śiva. This Viṣṇu is known as the Kṣīrodakaśāyī Viṣṇu, and He acts as the Supersoul in every living being. There are innumerable universes floating on the Causal Ocean, and in each of them the representation of the virāṭ form of the Lord is there along with innumerable suns, moons, heavenly demigods, Brahmās, Viṣṇus and Śivas, all of them situated in one part of the inconceivable potency of Lord Kṛṣṇa, as stated in the Bhagavad-gītā (10.42).
(Srimad Bhagavatam----2:1:28----purport).

Rāvaṇa was made a very powerful man by worshiping Lord Śiva, and he used to offer severed heads to please Lord Śiva. He became so powerful by the grace ofLord Śiva that all the demigods were afraid of him, until he at last challenged the Personality of Godhead Śrī Rāmacandra and thus ruined himself. In other words, all such persons who aspire after gaining some or all of the material objects of enjoyment, or the gross materialistic persons, are on the whole less intelligent, as confirmed in the Bhagavad-gītā (7.20).
(Srimad Bhagavatam----2:3:2-7----purport).

Brahmā and Śiva (and what to speak of other demigods) are bhūtas, or powerful created demigods who manage universal affairs, much like ministers appointed by a king. The ministers may be īśvaras, or controllers, but the Supreme Lord is maheśvara, or the creator of the controllers.
(Srimad Bhagavatam----2:4:6----purport).

This material world is a manifestation of the three modes goodness, passion and ignorance, and the Supreme Lord, for the creation, maintenance and destruction of the material world, accepts three predominating forms as Brahmā, Viṣṇu and Śaṅkara (Śiva).
(Srimad Bhagavatam----2:4:12----purport).

Brahmā is the representation of the mode of passion, and Viṣṇu is the representation of the mode of goodness, while the mode of ignorance is represented by LordŚiva, the father of material activities. Material nature is called the mother, and the initiator for materialistic life is the father, Lord Śiva. All material creation by the living entities is therefore initiated by the mode of passion.
(Srimad Bhagavatam----2:5:23----purport).

The Lord is nirasta-sāmya-atiśaya; in other words, no one is greater than or equal to the Supreme Lord. So the living entities, including even such great personalities as Lord Brahmā and Lord Śiva, are all subordinate to the Lord. In the material world also, in His eternal form of Viṣṇu, He maintains and controls all the affairs of the demigods, including Brahmā and Śiva.
(Srimad Bhagavatam----2:6:32----purport).

Brahmā, Nārada and Lord Śiva know about the Lord to a considerable extent, and therefore one should follow the instructions of these great personalities instead of being satisfied with a tiny brain and its playful discoveries such as spacecraft and similar products of science. As the mother is the only authority to identify the father of a child, so the mother Vedas, presented by the recognized authority such as Brahmā, Nārada or Śiva, is the only authority to inform us about the Absolute Truth.
(Srimad Bhagavatam----2:6:37----purport).

The Causal Ocean is created by the Lord as the mahat-tattva, as a cloud in the spiritual sky, and is only a part of His different manifestations. The spiritual sky is an expansion of His personal rays, and He is the mahat-tattva cloud also. He lies down and generates the universes by His breathing, and again, by entering into each universe as Garbhodakaśāyī Viṣṇu, He creates Brahmā, Śiva and many other demigods for maintenance of the universe and again absorbs the whole thing into His person as confirmed in the Bhagavad-gītā (9.7):
sarva-bhūtāni kaunteya
prakṛtiṁ yānti māmikām
kalpa-kṣaye punas tāni
kalpādau visṛjāmy aham
"O son of Kuntī, when the kalpa, or the duration of the life of Brahmā, is ended, then all the created manifestations enter into My prakṛti, or energy, and again, when I desire, the same creation takes place by My personal energy."
(Srimad Bhagavatam----2:6:39----purport).

One should know the Lord as much as can be known by our limited knowledge. It is impossible for the Lord to be known perfectly as He is, even by such liberated persons as Śiva or Brahmā, so what to speak of other demigods or men in this world. Still, by following the principles of the great devotees and the instructions available in the scriptures, one can know to a considerable extent the features of the Lord.
(Srimad Bhagavatam----2:7:3----purport).