Siva is Lord Krsna's greatest devotee.

Devotees of Lord Krsna honor Lord Siva for his celebrated qualities and his exalted status in the hierarchy of living entities.

Srimad-Bhagavatam is an amazing collection of the glories and activities of Sri Krsna and His devotees, the Vaisnavas.

In Srimad Bhagavatam (Bhagavat Purana) Canto 12 Chapter 13 text 16, declares Lord Siva to be the greatest of all Vaisnavas-  

Vaisnavanam yatha sambhuh. 

Lord Siva’s special position, his post, his personality, and his activities are fascinating to know, yet also mysterious and very hard to understand. 

The following is a short collection from the Bhagavatam of various attributes and activities of Lord Siva.

Siva has 85.938% of Krsna's qualities which means he has 55 of Krsna's 64 attributes.

Srila Prabhupada explains Lord Siva is NOT a marginal living entities (jiva-souls) either. 

The jiva-souls have only 78.125% of Krsna's qualities, which is having 50 of Krsna's 64 qualities.  

Therefore, both the individual jiva-souls and Lord Siva are NOT the Supreme Personality of Godhead who is exclusively Krsna. 

Siva's actual position is somewhere inbetween Krsna's direct expansion Visnu, who has 93.75% of Krsna's qualities (having 60 of Krsna's 64 qualities).

Because Visnu/Narayana are direct expansions of Kṛṣṇa, they ARE Krsna playing Himself in another role.

Krsna's first Visnu expansion is Lord Balarama who is Krsna's older brother in Kṛṣṇa lila. All the other Visnu expansions on the Vaikuntha planets and in the material world like Maha-Visnu, Garbhodakashayi Visnu and Paramatma are actually further expansions from Balarama.

The original childhood Krsna NEVER leaves Vṛndāvana in the spiritual world.

Viṣṇu/Narayana ARE the Supreme Personality of Godhead also, while Brahma eternally represents the marginal living entities (jiva-souls or jiva-tattva) who have 78.125% of Krsna's qualities (having 50 of Krsna's 64 qualities) as said above. 

Srila Prabhupada - "Lord Siva is explained in Brahma-samhita (5.45) as follows-

"kshiram yatha dadhi vikara-vishesha-yogat

sanjayate na hi tatah prithag asti hetoh

yah shambhutam api tatha samupaiti karyad

govindam adi-purusham tam aham bhajami"

Lord Siva is considered to be like yogurt (dadhi). Yogurt is nothing but transformed milk; nonetheless, yogurt cannot be accepted as milk. 

Similarly, Lord Siva holds almost all the powers of Lord Visnu, and he is also above the qualities of the living entity, but he is not exactly like Visnu, just as yogurt, although transformed milk, is not exactly like milk." (SB Canto 4 Ch 30 text 24, Purport)

Learned scholars in transcendental subjects have carefully analyzed the summum bonum Krsna to have sixty-four principal attributes. 

All the expansions or categories of the Lord possess three different percentages of these attributes. 

Visnu-tattva (93.75%) Krsna's first Visnu-tattva expansion is Lord Balarama then all others come from Him.

Visnu-"sakti"-tattva (93.75%) headed by Srimati Radharani and Krsna's eternal associates (His internal potency).

Siva-tattva (85.938%) Lord Siva, in a league of his own and is Krsna's greatest devotee.

Jiva-tattvas or marginal living entities (jiva-souls) (78.125%) headed by Lord Brahma and Narada Muni and their expansions (like Srivas in the Pancha-tattva who is also Narada Muni)

Srila Prabhupada - "Sri Krsna is the possessor of the attributes cent percent. And His personal expansions possess only up to ninety-three percent of these transcendental attributes. Lord Shiva possesses almost eighty-four percent of the attributes.” (SB Canto 1 Ch 3 text 28, Purport)

Lord Siva is considered the father of this universe, and material nature, or goddess Durga, is considered the mother. 

Siva is neither the Supreme Lord nor a jiva-tattva (jiva-soul), the category to which we (marginal living entities) belong. 

Siva is the personal form through which the Supreme Lord works to inject the living entities (jiva-souls) into this material world.

Lord Siva is in charge of the tamo-guna, the mode of ignorance, and is thus in the category of incarnations known as gunavataras. 

Srimad Bhagavatam - "Sukadeva Goswami said,  "The transcendental Supreme Personality of Godhead is indirectly associated with the three modes of material nature namely-

1 - passion, 

2 - goodness, 

3 - ignorance.

All 3 are part of the material world's 

creation, 

maintenance, 

destruction. 

He accepts the three qualitative forms of Brahma, Visnu, and Siva." (SB Canto 1 Ch 2 text 23) 

As the god of annihilation, Siva is responsible for destroying the universes during the partial and complete devastations, which occur respectively at the end of each day (only between sunset and sunrise night time hours where no Maha-yugas are created) of Brahma and at the end of his life.

Srila Prabhupada - "The dissolution of the three worlds is effected by the incarnation of darkness, Rudra [Siva], represented by the fire of eternal time which blazes over the three worlds." (SB Canto 3 Ch 11 text 28, Purport) 

Srimad Bhagavatam - "Sukadeva Goswami said, "Thereafter, at the end of the millennium, the Lord Himself in the form of Rudra, the destroyer, will annihilate the complete creation as the wind displaces the clouds." (SB Canto 2 Ch 10 text 43)

Siva’s Personality of Ashutosha is easily pleased very quickly.

Srimad Bhagavatam - "From being simple-hearted to being tricky, from being easily pleased to blazing with anger, Lord Siva displays many facets of personality, all in the service of his dear Lord Sri Krsna. 

He exhibits dependence on Krsna and His devotees as well, as surrender and service to them. One of the prominent attributes of Lord Siva is being quickly pleased with anyone. 

Amongst all the demigods, Lord Siva can be pacified even by the lowest class of men, who need only offer him obeisances and leaves of a bael tree. 

Thus his name is Ashutosha, which means that he is pleased very quickly. 

Being Ashutosha, Siva is approached by various types of beings – demigods, demons, pious and impious human beings, devotees of Krsna, and so on. 

However, as Lord Siva knows the intentions of everyone, he tricks the demons, satisfies the materialists, blesses the simple-hearted with devotional service to the Supreme Lord, offers heartfelt benedictions to devotees, and associates with advanced devotees. 

In this way Lord Siva blesses different people according to their position and at the same time exhibits his devotion unto the Lotus feet of the Supreme Lord Sri Krsna.

Siva’s Mercy on the Vaisnavas.

Although Lord Siva bestows benedictions upon devotees and demons alike, there is a gulf of difference in the way he blesses them. He is always pleased with the pure devotees of Lord Krsna he himself says-

yah param ramhasah sakshat

tri-gunaj jiva-samjnitat

bhagavantam vasudevam

prapannah sa priyo hi me

“Any person who is surrendered to the Supreme Personality of Godhead, Krsna, the controller of everything – material nature as well as the living entity – is actually very dear to me.” (SB Canto 4 Ch 24 text 28)

Srimad Bhagavatam - "How much he is pleased with Krsna’s devotees can be seen in how he sometimes appears before them even uninvited. For example, the Pracetas were the ten sons of Pracinabarhi, a king in the dynasty of Dhruva Maharaja. Before taking charge of the kingdom, they went to perform devotional austerities to please Lord Krsna. Knowing this, Lord Siva came before them to bestow his mercy upon them by guiding them in devotional service. Thus He taught them the Rudra-gita." (SB Canto 4, Ch 24)

Srimad Bhagavatam - "Lord Siva came to Markandeya Rishi, a great devotee of the Supreme Lord, glorified his devotional attributes, and gave him benedictions of knowledge, renunciation, realization of Krsna, and the post of spiritual master of the Puranas. (SB Canto 12, Ch 10)

Siva’s Mercy on the Demons and ghosts.

Srimad Bhagavatam - "Although Lord Siva is easily pleased and his mercy is easily available to Krsna’s devotees, demons and others have to undergo at least some endeavor to please him. He uses these demons to show his dependence upon his worshipable Lord Kṛṣṇa. He also tricks them by offering them benedictions that seem to favor them but ultimately lead to their destruction.

Salva, 

Ravana, 

Bana, 

Jayadratha, 

Kashiraja 

All the above were among the various materialistic and demoniac people eventually destroyed even though they had summoned Lord Siva by their austerities and received benedictions from him. Siva appears before demons in an official capacity, as required by his "post."

One example is the demon Vrikasura, who worshiped Lord Siva by offering pieces of his own flesh as oblations into fire. When Siva did not appear before him, Vrika prepared to cut off his own head. Then the supremely merciful Lord Siva rose up out of the sacrificial fire and stopped him, offering him whatever boon he chose.

Vrika said, “May death come to whomever I touch upon the head with my hand.”

Upon hearing this, Lord Siva seemed somewhat disturbed. Nonetheless, he was obliged to reciprocate and vibrated om to signify his assent, granting Vrika the benediction with an ironic smile, as if giving milk to a poisonous snake. Wicked Vrika tried to test the benediction by putting his hand on Siva’s head. 

Terrified, Siva fled and finally reached Lord Visnu in Svetadvipa. Visnu disguised Himself as a young student, went before Vrikasura, and bewildered him to put his hand on his own head, thus causing his destruction." (SB Canto Ten, Ch 88)

Srimad Bhagavatam - "Thus the benedictions Lord Siva gives to the demons generally end up glorifying Visnu as the ultimate protector. Siva thus takes pleasure in praising his beloved Lord.

Siva is also easily angered.

Another aspect of Lord Siva’s personality is his anger. He exhibits anger as part of his position as the destroyer of the universe. 

His anger, however, is born out of his compassion as well as his intolerance in seeing conditioned jiva-souls wasting time by not taking to devotional service.

In an episode related in the Fourth Canto, Lord Siva once exhibited anger toward Daksha, a leading progenitor in the universe. 

Although Daksha insulted Siva at a great sacrifice, Siva's anger was aroused not because Daksha insulted him but because Daksha later caused the death of Sati, his own daughter and Siva's dear devoted wife. 

When Siva heard from Narada Muni that Sati was now dead because of Daksha’s insulting her, Siva became greatly angry and created Virabhadra from his hair and ordered him to kill Daksha. (SB Canto Four, Ch 5)

Srimad Bhagavatam - "As a dutiful father and spiritual master of all beings, Lord Siva uses anger to rectify people. In the context of the Daksha episode, he told Lord Brahma that he doesn’t take the offenses of the demigods seriously, but punishes them only to reform them as a teacher. (SB Canto 4.7.2) 

In this way Lord Siva uses his anger in the service of the Lord to rectify the living beings and never for his own ends. Siva’s Benevolence (well meaning and kindness)

When the demigods and the demons churned the ocean of milk (Canto Eight), deadly poison came out in the beginning. 

Srimad Bhagavatam - "Being helpless, they all took shelter of Lord Shiva, offering him fervent prayers. Always benevolent toward all living entities, Lord Siva said to his consort Sati-

"It is my duty to give protection and safety to all living entities struggling for existence. Certainly it is the duty of the master to protect his suffering dependents. People in general, being bewildered by the illusory energy of the Supreme Personality of Godhead, are always engaged in animosity toward one another. 

But devotees, even at the risk of their own temporary lives, try to save them. My dear gentle wife Bhavani, when one performs benevolent activities for others, the Supreme Personality of Godhead, Hari, is very pleased. And when the Lord is pleased, I am also pleased, along with all other living creatures. Therefore, let me drink this poison, for all the living entities may thus become happy because of me." (SB Canto 8.7.38–40)

Srimad Bhagavatam - "Sukadeva Goswami relates, "Bhavani, who knew perfectly well Lord Shiva’s mood and capabilities, gave him her permission." (SB Canto 8.7.41) 

Srimad Bhagavatam - "Auspicious Siva drank the poison for the benefit of everyone. The poison created a blue line on his neck that it is now accepted as an ornament of Lord Siva.

Sukadeva Goswami comments-

tapyante loka-tapena

sadhavah prayasho jana

paramaradhanam tad dhi

purushasyakhilatmanah

"Great personalities almost always accept voluntary suffering because of the suffering of people in general. This is considered the highest method of worshiping the Supreme Lord, who is present in everyone's heart." (SB Canto 8.7.44)

Thus Lord Siva’s attributes of mercy, anger, and benevolence and his various activities display his great character and devotion to the Supreme Lord Visnu. 

In his great devotional ecstasy, he even holds on his head the water that emanates from the lotus feet of the Supreme Lord (the Ganges). 

Lord Siva is the epitome of devotion to Visnu, and thus is the topmost Vaisnava