It is narrated from Sayyiduna Ka'b bin Malik (may Allah be pleased with him) that when his excuse was revealed (in the form of the acceptance of his repentance), he came to the Prophet (peace and blessings be upon him), took his (peace and blessings be upon him) hand and kissed it.
Hadith Referenceالمعجم الكبير للطبراني / باب الكاف / 16236