Often when meditating, no matter how experienced we might be, the mind keeps wandering off and we have to call it back. I am reminded of training our cavalier spaniel who would keep darting off in different directions, and each time I would have to say ‘Heel!’ Patiently of course. Shouting does no good.
So now, whenever my mind wanders, I mentally say ‘Heel!’
But when our mind does dart off, it is important not to squash the thought: it may be quite innocuous, or it may contain some bitterness, resentment or anger that suddenly wells up. We need to look at it dispassionately, acknowledge it, and then return to our meditation. We will find that over time the bitterness or anger, or whatever, will gradually dissolve.