It is permitted to narrate hadīth by meaning because we do not worship Allah  by the words of a hadīth but by its meaning because the wahy (revelation) is the meaning of the hadīth and not its words. However, it has been stipulated that the narrator be knowledgeable about anything that can change the meaning. If he is not knowledgeable or cognizant of that then it is not allowed to narrate hadīth by meaning. As for the abridgment of the hadīth it is allowed. It is allowed to narrate a hadīth in an abridged form with a part omitted and a part mentioned on the condition that the omitted part does not relate to the part mentioned. However, it is not allowed to omit or exclude the objective (gaya) and other such things which would make the meaning deficient or make the part of the hadīth which has been mentioned lead to a meaning which is completely contrary to the (actual) meaning of the hadīth. If the objective (gaya) or other such matters in the narration are secondary and there is doubt in the narration then it is obligatory to narrate the part which is reliable and the part that is doubted is removed.