Pirkei Avot - Ethics of the Fathers

~Level 1~
Bartenura - "morning sleep" - he sleeps until the time of reciting the Shema passes

"mid-day wine" - it draws a person's heart as written: "I searched in my heart to draw my flesh with wine" (Kohelet 2), and brings him to drunkenness.

"children's chatter" - they annul their father from toiling in torah.

"sitting in the assemblies of the unlearned" - they come together and speak useless talk.

~Level 3~
Tiferet Yisrael - he mentioned four things very needed for one's health and wholeness but if he is not careful in them, he will lose his world due to them.

"[late] morning sleep" - i.e. the heaviness of laziness. Sleep is necessary for one's health.. but after he had a night's sleep, there is no excuse (for not waking up).
This refers to running after pleasures which are not necessary to strengthen the body.. excessive wine (pleasures) will confound his mind, make his body feel heavy, etc. and cause that for the rest of the day, he will have no desire for torah and wisdom.

"children's chatter" - i.e. laughter and joking. A little bit is good to calm and bring joy to the soul. But only with adults. For their joking has things of [sound] mind. But talk with children is most likely joking and laughter of things devoid of knowledge and understanding and it will not bring joy to the soul. On the contrary, it will confound the ways of the mind.

"sitting in the assemblies of the unlearned" - i.e. useless talk. Here too a little is good after a person has toiled in wisdom. It is proper for him to mingle a bit with friends to calm the mind just like the body rests with sleep. But with the ignorant, they will speak slander and profanities or the like, things devoid of intellect, fear of Heaven, or any other benefit of mussar or wisdom. There the soul will not rest. Rather a strange fire will burn it.

On these four things, the Tanna well said that they remove a person from his world and eternity, i.e. even if he is already there (on the good path).

~Level 3~
Rabeinu Yonah - "removes a person from the world" - for why was man created? Only to toil in torah. It is "his years of and the length of his days". But if he goes after these other things, why should he have life? It is proper to remove him from the world. For he is vanity and his days are vanity. After he lived some days and toiled in useless things and annulled the torah, why should he be given additional days? It is analogous to a king who gives his servant 100 silver coins and the servant casts them into the sea and afterwards asks the king for more - it is proper for the king to not give him any more! So too for one who does not toil in torah.

~Level 3~
Rabbi Avraham Azoulai - Ahava b'Taanugim - "morning sleep" - as known, there is no better time where one is ready for the service of G-d like the morning. For the stomach is empty of food and the mind is settled for the service, and all the more so since it is the time of reciting the Shemah and the prayer of the congregation is accepted. Then it is a favorable time for his prayer to be accepted to annul all bad decrees from himself.

But he who sleeps at this time demonstrates his laxness in seeking his wholeness and rectification and that he goes after the advice of his evil inclination. He cannot conquer his evil inclination to get up from his bed. Rather, he desires (chafetz) the advice of his evil inclination. Certainly, he is liable for his life and he wants to slay his soul with his own hands. His blood is on his head.

This itself is the reason for "wine".. That he goes after the superfluous for no avail.. and likewise for children's chatter. For the mind of a whole man cannot bear to waste his time in useless words (divrei havai) like children's chatter which has no benefit for the soul. And all the more so when they jest and he abandons the torah and sits in a sitting of jesters. This certainly demonstrates on his evil intent in all his deeds - he does not seek the wholeness of his soul and he slays himself and is liable for his life.

This itself is the reason for sitting in the assemblies of the amei haaretz (ignoramuses). Certainly there are no words of torah between them. Rather, only lashon hara (slander) and leitzanut (jesting), and to learn bad character traits from them.. All these four things are bad beginnings which the yetzer entices a man towards and tells him that there is no torah prohibition, etc. But they are a poisonous root to lose one's wholeness and become liable for his life.

~Level 4~
Maharal - "removes a person from the world" - for all these things are pursuit of the bodily matters which is removing oneself from Torah. Therefore, they remove a person from the world. For the torah is man's life (chiyuto). And when a man turns to things like these - it is removing oneself from life.

Earlier, he said "one who forgets one thing from his [torah] studies..", i.e. even if he does not do a thing, but just sits idle, it is considered as if he is liable for his life. For he removes words of Torah from his heart. But if he actively does an act like these four things mentioned, namely, morning sleep, afternoon wine, etc., then even if he does not forget his learning, nevertheless, because these things are complete removal from the Torah through turning after lusts and the vanities of the world, it is considered complete removal from the Torah which is man's life. Thus, he is removed from the world...

"morning sleep" - this when a man is drawn after morning sleep, he is drawn excessively after the body. For when a man sleeps, he is completely physical and all his powers of the soul are annulled and nothing is left except his body. Thus, he becomes completely physical.. And turns after the body and the inexistence..

"mid-day wine" - he sins in the second part of man, the nefesh (soul). For "wine rejoices the heart" whic refers to the soul in man. And "mid-day wine" rejoices excessively.. until he is completely merry.. And this is certainly a lacking and inexistence. For all excess is like lacking and inexistence. Therefore, this removes a person from the world.

"children's chatter" - this corresponds to man's third part, namely, his intellect. For children's chatter is the opposite of the talk of elders in wisdom. Children's talk is of vanity, laughter, and confusion. Therefore, "children's chatter" is a departure from wisdom. This is certainly a complete lacking and inexistence...

"sitting in the assemblies of the unlearned" - this corresponds to the fourth part we mentioned. Namely, that man is part of a congregation.. The assembly of the unlearned is the opposite of an assembly in a synagogue in matters of holiness. For it is of useless matters and not considered of real matters... (see there for more).