Radha undoubtedly was closest to Krishna’s heart. He loved her over and above everything. However, this filled Radha with unprecedented pride which Krishna did not approve of. She was habituated of receiving excessive attention from Krishna.
One day, Krishna, trying to play on her vanity, suggested Radha to steal away together with him, to which Radha readily agreed. He said he wanted to spend time with her alone. Radha felt highly important and favored as she was enjoying every bit of this attention. So they began walking together, Krishna not wanting to stop anywhere in the middle to rest. Radha, having gotten tired, suggested they had reached a nice spot where they could spend time alone. Krishna did not agree and said they should find a better spot, hence the two kept walking.
After walking for quite some time, Radha gave up and said she was too exhausted to walk any further. To this, Krishna offered Radha to climb on his back. Radha was overjoyed. As she sprung on his back Krishna disappeared. She fell on the ground like a heap. Her entire pride got shattered in seconds.
Radha understood her mistake. She was on her knees pleading the lord to forgive her for wanting to control and possess him.Krishna appeared in front of her and blessed her. She had learnt a very important lesson of life that day, that she should not try to control her master and look upon him as an ordinary man who could be tamed as per her whims and fancies. She had understood well that Krsihna was the last person on earth who could be controlled and entangled by feminine wiles. She even realized that Krishna was interested in beauty of her soul and not on her physical beauty.
Krishna is Omni-present. He cannot be restricted and controlled by a single individual, be it his most ardent devotee. He loved Radha to the core, yet he was not ready to be controlled by her. He broke her pride and made her understand that love is to let go and not try to bind it with conditions and promises