Bhakt vatsal-Shri Krishna
Shri Krishna’s love for his devotees is unfathomable. that is why he is called Bhakt Vatsal (Devanagari: भक्त वत्सल ISO15919: bhakta vatsala).
Shri Krishna's dominion
There are countless brahmands in the vast sansar. Our scriptures tell us that,
संख्या चेत रजसामस्ति न विश्वानां कदाचन ।
sankhya chet rajasaamasti na vishvaanaan kadaachan
“Even if it were possible to count the infinite tiny particles of dust on this earth still it is impossible to count the number of brahmands in God’s creation”.
Each brahmand has three governors - Brahma, Vishnu, Shankar.
All these countless brahmands are surrounded by a divine river called Birja Nadi(river). Beyond that river is a divine area called Paravyom Lok.
Shri Krishna is the supreme governor of all material and divine realm. He is Brahm - Supreme God – Superior-most (Paratpar) amongst all The Supremes.
As once Narad Ji said to Him, in a lovingly teasing manner
परम स्वतन्त्र न सर पर कोई । भावे जोई करै सोई सोई॥
parama svatantra na sara para kōī । bhāvē jōī karai sōī sōī॥
"You are supremely independent. That is why you do whatever you wish”.
The Vedas say -
कृष्णो ह वै हरिः परमो देवः ।
kr̥ṣṇō ha vai hariḥ paramō dēvaḥ ।
“Shri Krishna is the Brahma - Supreme God”.
न तत्समस्चाभ्यधिकस्च दृश्यते ।
na tatsamascābhyadhikasca dr̥śyatē ।
“Let alone be greater, none is even equal to Him”.
Shri Krishna's Providence
But Shri Krishna says all the theories that I am self-willed, supremely independent and greatest are false.
Why?
Because even though the innumerable brahmands and their governors remain under my control yet I am a bonded slave of my fully surrendered devotees.

There is a story in Bhagawat when Rishi Durvasa decided to mistreat Lord Krishna’s surrendered devotee king Ambarish. Shri Krishna warned Durvasa -
अहं भक्त पराधीनो ह्यस्वतंत्र इव द्विज । भा. ९.४.६३
ahaṁ bhakta parādhīnō hyasvataṁtra iva dvija ।
bhā. 9.4.63
“O Brahmin! Although I am completely independent yet I am under the control of My devotees". Just like one of my powers Maya makes the entire world dance to its tune, my devotees make Me dance to their tune.
Rishi Durvasa didn’t pay heed and went to show off his might to king Ambarish. King Ambarish and his queen were performing great austerities. For twelve months they had been fasting on every ekadashi. Their austerities was about to end. On the morning of the last day of austerities, Rishi Durvasa and one hundred of his disciples arrived at King Ambarish's palace.
Ambarish was overjoyed and welcomed the saints. Also, he requested the saints to accept a banquet. Rishi Durvasa agreed but wanted to perform mid-day ablution before accepting the meal.
Rishi Durvasa and his disciples hadn't returned and the opportune time (mahurt) for breaking the fast was about to end. The king's priests advised him to eat a leaf of Tulsi plant with a sip of water to break the fast. Ambarish followed their advice.
Rishi Durvasa, with his mystic powers, knew that Ambarish had broken his fast without first offering the food to the saints.
Enraged he reached Ambarish's palace. Ambarish folded his hands and sought apology but Rishi Durvasa would not relent. Rishi Durvasa decided to punish Ambarish for his impertinent behaviour. He plucked out a hair, turned it into a demoness Kritya and commanded her to eat Amabarish. Amabarish didn't resist instead he stood politely with his folded hands.

Saints consider themselves a soul and realize the impermanence of the body. So they remain unfettered by anything that might happen to the body. But, Shri Krishna, seeing His devotee in trouble could not bear it and set His Sudarshan Chakra after Rishi Durvasa.
First, Chakra burnt the demoness to ashes, then moved towards Rishi Durvasa to burn him as well. Seeing Sudarshan moving towards himself, Durvasa was frightened and ran for his dear life. Rishi Durvasa went to all the planets in an attempt to save Himself, but he could not get rid of the Sudarshan Chakra .

He tried to seek refuge from Lord Brahma, Lord Shankar and other sovereign personalities, but none could grant refuge against Lord Shri Krishna's Chakra.
Finally, he was advised to seek protection from Amabarish. Upon request from Amabarish, Sudarshan Chakra forgave Durvasa and retreated. Saints have a very tender heart. If anyone honestly apologizes they are quick to overlook the offense and forgive.

Shri Krishna's Love
Shri Krishna says -
न तथा मे प्रियतम आत्मयोनिर्न शंकरः । न च संकर्षणो न श्रीर्नैवात्मा च यथा भवान्॥ भा १.१४.१५
na tathā mē priyatama ātmayōnirna śaṁkaraḥ । na ca saṁkarṣaṇō na śrīrnaivātmā ca yathā bhavān॥
bhā 1.14.15
“I don’t love my son Brahma, my brother Balram, my wife Lakshmi". People love their spouse the most. Yet Shri Krishna says,"I don’t love my wife Mahalakshmi as much as I love my devotee”.
In fact, He goes even one step further to say,
र्नैवात्मा च यथा भवान्॥
rnaivaatma ch yatha bhavaan.
“My devotees are dearer to me than my soul itself”.
Servants are dear, friends are dearer, parents and children are even dearer. Spouse is the dearest. Still more dearer than the spouse is our own body.
Imagine a couple is proceeding towards each with outstretched arms with great lust. As they are about to embrace throw a plastic snake in between them. Then observe how they run in the opposite directions screaming in fear. It proves we care for our body a lot more than even the spouse.
Mind is even more dearer than the body. There is nothing dear than the soul (the real I).
Shri Krishna loves His devotees even more than He loves Himself. It is for this reason that He takes utmost care of his devotees. That is why He is referred to as Bhakta Vatsal. He asserts in Gita with challenge,
न मे भक्तः प्रणष्यति ।
na mē bhaktaḥ praṇaṣyati
“My devotee cannot falter because I assume full responsibility of My devotee”.
At the time of God-realization, Lord Shri Krishna pardons all past sins of His devotee and assumes full responsibility of the devotee's actions in the future, and as if that was not enough, He goes on to render His personal services to them. He becomes their slave.

You must have heard numerous stories of Shri Krishna serving His devotees by picking up cow dung for the gopis, picking up and bringing footwear of Nand Baba on His head, upon loosing a bet becoming a horse for his friends to ride on and letting them kick him in His stomach to run faster.
Who can fathom this infinite ocean of love that Lord Krishna has for His devotees!
Glories be to Bhakt Vatsal Shri Krishna!!!
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