It is described in the Visnu Purana that when Akrura came to take Krsna and Balarama to Mathura, just by seeing Their faces he became so cheerful that all over his body there were symptoms of ecstatic love. This state is called happiness.
It is stated in the Tenth Canto, 33rd Chapter, 12th verse of Srimad-Bhagavatam: "Upon seeing that Krsna's arm was placed on her shoulder, one of the gopis engaged in the rasa dance became so ecstatically happy that she kissed Krsna on His cheek." This is an instance of feeling happiness because of achieving a desired goal.
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