Aparadvadashamuhurta vedaniyasya (18)
Karma that determines our feeling of life (vedaniya) will remain bound to us for a minimum of 9 hours and 36 minutes (12 muhurtas). (18)
One muhurta lasts about 48 minutes. 12 muhurtas are 12x48 minutes or 9 hours 36 minutes.
Karma that determines our feeling of life (vedaniya) can dissolve earliest 9 hours and 36 minutes after we bound it.
As academic as this may sound, as vital and practical it is for our daily life. One example: We experience a strong negative emotion whose origin we attribute (arbitrarily) to a person in our close environment. Instead of reacting immediately and impulsively on the basis of our negative emotional sensation - and thereby possibly hurting someone innocent, - we would be well advised to wait a minimum of ten hours (to sleep over it) before we act. This would give our negative emotion the opportunity to dissipate - our karma a chance to dissolve - and prevent possible repercussions any premature, impulsive action of ours may have.
Knowing that karma will affect us for at least a minimum time before its influence ceases, gives us vital information about its mechanism of dissolution.
If in the above example we would act spontaneously on our negative impulse and hurt the other person, we would attach ourselves to more karma of the same kind. Thus the very basis for our negative emotions would be reinforced and the reoccurrence of our uncomfortable feelings inevitably programmed for the future.
Yet if we know that any negative emotion is nothing other than the activation of our own karma and that this karma will affect us only for limited time, we can easily wait patiently until this time is over. When - after the respective period has passed (in this case 10 hours) - we notice that our negative emotions are gone, we then have confirmation that the tinge of our feelings is our very own responsibility and that it is useless to attribute the cause of our negative emotions to someone else.
Karma may not necessarily be active during the entire minimum period it is bound to our interactive karmic field.