Observing the fight between the disappointed groups of suitors and the Pndava brothers,Krishna and Balarma were smiling within themselves in appreciation of the successful feat of Arjuna. Your grandfathers had no knowledge who they were; they had not seen them any time previously.
But when the Pndavas reached their residence, the humble home of a potter, with the newly-won bride, the daughter of Drupada, and when Dharmaraja, the eldest brother, was describing with great exultation the events of the day, Balarma and Krishna, dressed inyellow silk and magnificent to behold, entered that lowly cottage. They fell at the feet of agedKunt, mother of your grandfathers. "Auntie! We are your nephews", they said. "We are the children of Nanda and Yas'od", and introduced themselves. Then, they touched the feet ofDharmaraja, prostrating themselves before him. Krishna approached Arjuna and drew him aside, with a sweet simple expression of affection. "I know you, but you do not know me,I am seeing you now for the very first time. I am the son of Vasudeva, my name is S'r Krishna. I am younger than you are; still, when you achieved that victory in the Royal Palace, I recognised that you are one of the Pndava brothers and so, I understood that you had escaped from the palace of lac wherein you were when it was set on fire. From the moment my eyes fell on you at the gathering of suitors there, I somehow felt that you are Arjuna; I told my brother so. This is my brother, Balarma. I was very happy that I recognised you and my brother too shared the joy. At last, I am able to meet you. The bride is the embodiment of virtue and intelligence."
Speaking thus, Krishna called Arjuna to a distance and whispered in his ear, "Cousin! It is not advisable that you come out in the open so soon. Stay on in disguise, for short periods, in one place or other, for some more time". Then, He took leave of His aunt and others and left, with His elder brother Balarma.
From that day, the affection between Krishna and Arjuna grew more and more intense; it grew into a huge tree and yielded fruits rich with sweetness, which they shared. In that sweetness, their minds merged and became one.
Mark! The first time your grandfather met Lord S'r Krishna, He was at the Wedding Hall of Draupad, the Kalyana Mantapa. The significance of this lies in the fact that they too were bound throughout the years in bonds of love and affection of unfailing friendship. To consummate that friendship, Krishna taught him the highest wisdom. "Did you note how chummy that consummate trickster was with your grandfather?" With that question, Vysa rose and collected his things, in an attempt to depart.
Observing this, Parkchit pleaded piteously, wiping the tears of joy that filled his eyes, "Master! You have made the Lord stand clear before me, with your description of His ll and His grace. Please tell me more of the many occasions on which the Lord showered His mercy on my grandfathers, how He moved close with them and rescued them from calamity; sleep is deserting my eyes and prompting me to listen to the stories of God. Make this night holy by relating to me the glory of the Lord. That alone can give me satisfaction. Let me spend the night in His thoughts..., your silence is causing me great agony."
Vysa saw the steadfastness and devotion of Parkchit and changed his decision. He said,"Son! Were the mighty miracles of Krishna one or two in number, I could have described them to you. If one had a billion tongues, and the whole of eternity before him, description of His majesty can never be exhausted. All the Gods bowed before Him with folded hands. Sometimes He would raise His bhaktas to the skies; very soon He will drag them down into the depths. He treated the world as a puppet show. He was always radiant with His smile. He never knew anxiety, disappointment or distress.
He behaved sometimes like a common man, sometimes as an innocent child, at other times as a near kinsman, or as an intimate friend, or as a masterful monarch. Sometimes He behaved as a playful cowherd boy. He had the capacity and cleverness to play all roles with unique distinction.
He loved your grandfather, Arjuna, with special fervor.
He used to take him with Him, whatever the occasion or place. Arjuna could move about freely even in the inner apartments of the residence of the Lord.The Lord used to play with your grandfather in the waters of the Yamun, diving at one place and rising at a distant spot to surprise him, calling on him to do likewise if he could, competing with him in various games, games which defy description and identification.
All of a sudden, He would take Arjuna to a solitary place and converse with him there on some mysteries. He used often to discard the smooth silken bed and sleep with His head on Arjuna's lap instead.
Your grandfather too, reciprocated that love to the full. Though sometimes they were found angry against each other, talking as if they were enraged, they made up very soon and resumed friendly conversation quickly. My dear son, it can be said that they were Nara and Nryana, like the body and the breath; there was no Arjuna without Krishna and no Krishna withoutArjuna. There was no secret which your grandfather did not share with Krishna or which Krishna did not share with your grandfather. Which particular episode in their relationship am I to tell you now? Ask me any one which you would like to hear and I shall gladly relate it to you."
Chapter 18, Bhagvatha Vahini

(Bhagavad-Gita----18:65----purport).