What is the clarification of the hadith: "Whoever dreams a dream that he has not seen will be tasked to tie two barley grains together, and he will not do it"?

The general meaning of the hadith is the condemnation of lying in a dream. As for the detailed meaning, it is that whoever claims to have seen a dream which he did not see will be burdened on the Day of Resurrection with tying two barley grains, which is an impossible task and a punishment for him. The punishment for this lie is more severe than lying while awake, because a truthful vision is a part of prophethood, and the liar in it claims that Allah showed him what He did not show him, and this is a greater lie against Allah than lying against creation.