The Gemarah says that the fire of Gehenom has no rule over Talmidei Chachamim and also it has no rule over the sinners of Israel.
The implication of the Gemarah statements are :
1) Talmidie Chachamim are also admitted to Gehenom , althought they my not be affected by the fire.
2) Talmidie Chachamim may still have to pay their dues for Averots that they did in this olam . Perhaps the Gemarah does not imply that they can be admitted to Gehenom at all ,but this will not fit with the next statement regarding reshaim of Israel.
The Gemarah did not mentioned Sadikim but Talmidie Chachamim ,translated as Torah scholars .. we see that in previous Gemarah and Tosfa regarding Ahitofel and Doueg Hadomi.
3) Both Talmidie Chachamin and Reshaim are admitted to Gehenom and are not affected by its fire? That needs explaining.
Regards;
The Gemara in Sotah (21a) states that Torah saves one from sinning. Consequently, it is because of his immersion in Torah in his lifetime that the fire of Gehinom has no effect on a Talmid Chacham (this is only true, though, for one who learned with pure intentions, and not for one who learned Torah in order to persecute others or for one who had ulterior motives when he began learning, as we see from the story of Acher (Chagigah 15b)). Such a person does not enter the judgment of Gehinom at all.
However, if he sinned, he obviously will be judged for his sin, but after the judgment of Gehinom purifies him of his sin, there remains no effect of Gehinom at all.
Regarding your question what is the difference, then, between Talmidei Chachamim and Posh'ei Yisrael, see what we wrote at length in the Insights on this topic (which we are including below for your benefit).
All the best,
Mordecai Kornfeld
3) AGADAH: WILL TALMIDEI CHACHAMIM AND SINNERS HAVE THE SAME FATE
QUESTION: The Gemara says that the sinners of Yisrael, Posh'ei Yisrael, will not be burned by the fire of Gehenom, just like the gold upon the Mizbe'ach was not burned by the fire that burned there each day.
This statement is difficult to understand, because the Gemara earlier says that Talmidei Chachamim are not burned by the fire of Gehenom, as is derived from a Kal v'Chomer from the salamander. Just like the salamander comes from fire and its oil is fire-proof and protects a person's skin from fire, certainly Talmidei Chachamim -- whose entire bodies are fire -- will be protected from the fire of Gehenom. How can the Gemara place Talmidei Chachamim and Posh'ei Yisrael together in the same group, and say that neither will be affected by the fire of Gehenom?
ANSWER: TOSFOS YESHANIM (Eruvin 19a) answers that although the Posh'ei Yisrael will not be burned by the fire of Gehenom, nevertheless their faces will become blackened from it. Talmidei Chachamim, on the other hand, will not be harmed at all by the fire.
The source for this seems to be the Gemara in Rosh Hashanah (17a) which says that there is a type of sinner who will be punished by being dipped into Gehenom and immediately taken out. The Gemara there concludes that even though those sinners are not burned, their faces become blackened like the bottom of a pot from the fire of Gehenom. Similarly, the Gemara in Eruvin (19a) says that the reason Posh'ei Yisrael are not burned in Gehenom is because when they are judged to be sent to Gehenom, Avraham Avinu comes and lifts them up from there. After being there for a short period their faces are also blackened, just like the sinners mentioned in Rosh Hashanah. The Talmidei Chachamim, though, are not sent to Gehenom in the first place.
The underlying reason behind this could be as follows. The Gemara (Berachos 17a) says that inherently, it is our desire to do Hash-m's will, but there are external factors which prevent us from doing His will -- the Yetzer ha'Ra and subjugation at the hands of the nations. This inner desire to do Hash-m's will is expressed in the well-known ruling of the RAMBAM (Hilchos Gerushin 2:20-22), who says that if a sinner refuses to give a Get to his when he is required to, the Beis Din may strike him until he says, "Rotzeh Ani" ("I want to!"). The Rambam explains, based on the Gemara in Kidushin (50a), that in one's heart, even the Rasha wants to do the will of Hash-m, and it is just external temptations and impediments that prevent him from doing so. Therefore, when he says "Rotzeh Ani," we consider his words to be coming from his inner desire, and that is why we may rely upon them and consider his giving of the Get to be done willfully and not under coercion.
That is what the Gemara means when it says that "the Posh'ei Yisrael are filled with Mitzvos like a pomegranate." Underneath their external shell, they are filled with Mitzvos, but they have physical lusts that prevent them from doing the will of Hash-m.
The reason Jews have this inner desire to do Hash-m's will is because they inherited their traits from their forefathers, Avraham, Yitzchak, and Yakov. The Gemara (Yevamos 79a) says that the Jewish people are ingrained with certain good character traits, which they received from their forefathers, the Avos. This is what the Gemara in Eruvin means when it says that Avraham Avinu rescues the sinners from Gehenom. The Midos that they inherited from Avraham Avinu save them from Gehenom, for their inner desire was to do Hash-m's will. (However, the Gemara there adds that their rescue depends on their still identifying themselves with the Jewish people, even though they sinned. If they do not identify with the Jewish people, such as one who marries a Nochri, they lose the Midos that they inherited and are not saved by Avraham Avinu.)
What does the Gemara mean by saying that the faces of the sinners become black? Perhaps we can say that the face represents the body, the external appearance of the person (in contrast to the soul; see Megilah 14a, "Hem Lo Asu Ela l'Fanim ). The body is the source of the external lusts that prevent one's inner will to serve Hash-m from being carried out. As such, the body must be punished. The Gemara (Shabbos 152a) says that the destruction of the body is part of the Din of a person. (That is why the Din lasts for twelve months, for it takes twelve months for the body to decompose, Shabbos ibid.) Decomposition of the body is a reflection of the judgment of Gehenom. The Neshamah of the sinners, however, is pulled out of Gehenom -- the Neshamah does not have to be destroyed (the Gemara in Rosh Hashanah says that they are other types of sinners who do have to have their Neshamos destroyed). This type of sinner only has his body destroyed, because his body was the source of his sins.
On the other hand, the Gemara (Bava Metzia 82b) teaches that the bodies of Tzadikim are not affected by decomposition in the grave, and their bodies remain complete and after interred. Since the Tzadik's bodily passions did not mislead him and cause him to sin, there is no reason to punish his body.
This is why our Gemara says that "the bodies of Talmidei Chachamim are fire," and therefore even their bodies are not destroyed in Gehenom. In contrast, the bodies of Posh'ei Yisrael do have to be destroyed, as the Tosfos Yeshanim writes, and only their Neshamos -- which are compared to the gold upon the Mizbe'ach, due to the Kedushah of the Neshamah -- are not destroyed, because their inner desire was to do the will of Hash-m. (M. Kornfeld)