(Baraisa): If he is believed for Taharos, he is believed for Maaseros (even if he didn't specify it as part of his acceptance).

R. Yannai bei R. Yishmael taught it and explained that this is only when the Chaver is a guest of the Am HaAretz (he will certainly tithe whatever he eats), but when the Chaver is selling to the public, he is not believed until he publicly accepts to be careful.

(R. Zeira/ R. Yasa citing R. Yochanan): Even if a Chaver sends produce to another Chaver, he must tithe it beforehand.

Question (R. Zeira to R. Yasa): If I send to Rav Shmuel bar Rav Yitzchak or he sends to me, (must we tithe beforehand)?

Answer (R. Yasa): What can you prove from R. Shmuel bar Rav Yitzchak? (He is different to others) - whatever he eats, he is careful to buy already tithed.

If a man is trusted but his wife is not, one may buy from him but not be a guest at his home; but Chazal said that it's like living with a snake in a basket (as his wife will cause him to stumble).

If a wife is trusted but not her husband, one may be a guest at their home but one may not buy from him; but Chazal said that cursed is a person whose wife is trusted and he is not trusted.

Baraisa: A Chaver should not serve at the celebration of an Am HaAretz, nor the meal of an Am HaAretz (as people will see him and assume that the food is tithed), unless everything was already tithed by the Chaver. He should even tithe the barrel of wine that's used as the wine supply of the meal (rather than wait to tithe until he brings the wine to the table.)

If a Chaver did serve at the celebration or meal of an Am HaAretz, it can be assumed that he did tithe.

If they saw him sitting at the Am HaAretz's meal, it is not an indication that all of the food is tithed; perhaps he tithed for himself in his mind onto other produce.

If his son is sitting with him, the father must also tithe for his son's food (and the son can rely on his father). However, the Chaver is not required to tithe for anyone else, so another person must tithe for himself.

(Mishnah): If a person accepts upon himself to be a Chaver, he should not sell to an Am HaAretz whether wet or dry produce, and he should not buy from an Am HaAretz wet produce, nor be a guest at his home (even if the produce is tithed, due to the problem of Tumah), nor should he host the Am HaAretz, unless the Am HaAretz changes out of his regular (potentially Tameh) clothing.

(R. Yehuda): In addition, he should not breed small animals (such as sheep and goats) and he should not be unrestrained in making vows and in light-heartedness; he should not become impure from corpses and he should serve Chachamim in the Beis Medrash.

(Chachamim disagree): Those things are not related to Taharos (retaining the purity of items).

(Gemara): (The Mishnah taught that) he may not buy wet produce from him but he may buy dry, as Amai HaAretz are believed to say that something didn't get wet (making it susceptible to Tumah).

Support (Baraisa): An Am HaAretz is believed to say that these fruits did not become susceptible to Tumah; but he is not believed to say that they are susceptible but did not actually receive Tumah.

Question: (In the Mishnah, R. Yehuda taught that he may also not breed small animals.) From his wording it seems that he agrees with everything listed before this (including not staying at the home of an Am HaAretz). If so, doesn't it disprove R. Yona, who (when explaining R. Yehuda in the Mishnah,) said that Chaverim are not suspected of eating or feeding others untithed produce?

Answer: The reason not to be a guest at his home is (not because of untithed produce but rather) to prevent him from becoming Tamei and then making Taharos Tamei.

Question: Doesn't this also disprove R. Yosi who said that Chaveirim are suspected of eating (untithed produce) but not of feeding it to others. (And here, R. Yehuda doesn't even allow a Chaver to be a guest at the home of an Am HaAretz?)

Answer: (As in the previous answer, being a guest brings a concern) for Taharos, but the concern here is for untithed produce; (as we saw earlier), that one who is believed for Taharos is believed for Maaseros.

Baraisa: Whoever want to become a Chaver must accept upon himself in public (as listed in the Mishnah); even if he is a Chaver Torah scholar; but an Elder who taught Torah in public does not need to make this acceptance, because as soon as he sits to teach, he has already made it.

(R. Ila): It is assumed that he already accepted it earlier (but if it is known that he did not, he must accept it in order to be trusted).

Question (R. Yosi): Isn't it true for everyone that unless they accepted earlier, they must accept in order to be trusted?

Question #2: R. Ila is like Reish Lakish, who would go to these people of the House of R. Yanai and when they saw him, the women ran away so that they should not make him impure from their clothing. He said to them, "I am able to come to your houses (and there is no need for you to run away), because I am also categorized as an Am HaAretz in Taharos, (since I never accepted to become a Chaver).

(Baraisa): One who wants to become a Chaver must stand in front of 3 Chaverim. His family members must merely agree at some point before him and they have no need for their own separate acceptance.

(Another Baraisa): His family members must accept with him in front of 3 Chaverim.

Resolution: It depends whether or not the children are supported by their father.

Baraisa (R. Chalafta ben Shaul): Adult children of a Chaver must accept in front of 3 Chaverim; young children accept in front of him.

Baraisa: One who wishes to become a Chaver - we first teach him about 'Knafayim' and then we teach him about 'Taharos'.

(R. Yitzchak b'R. Elazar): 'Knafayim' refers to Tumah through touching and pushing; 'Taharos' refers to Maaseros.

Originally, they would say that if a Chaver became a tax collector, we remove his Chaver status; and when he stops the job, he is reinstated as a Chaver.

(Chiya bar Bun citing R. Yochanan): If a Chaver went to Chutz LaAretz, we do not automatically remove he status of Chaver, so when he returns, he does not need to reaccept it.