In the hadith of Rasool Allah, s'Allahu alayhe wa salam, (Sahih Muslim) he stated that we should not shave part of the hair and leave the other part. (Sorry for the loose translation.) I have always trimmed my son's hair longer on the top and shorter on the sides. Does the hadith mean different levels or actually shave (no hair)? Please clarify this for us.

Praise be to Allah, the Lord of the Worlds; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. Qaza‘ (stray of hair) means to shave a part of one’s head and to leave another. At the same time, if one has one’s hair cut in such a manner that there is a very clear difference between one part of one’s head and another, then this is also Qaza‘. In fact, both forms are not permitted in Islam, especially if one follows this as an imitation to Non-Muslims. Ibn ‘Umar () says that The Beloved Prophet (Blessings and peace of Allah be upon him) “had has forbidden shaving only a part of the head and leaving unshaved another part.” And Allah knows best.