Standing for a Talmid Chacham and for the elderly
- There is a positive mitzvah Deoritta to stand up for a Jew who is 70 years old. If one is unsure if the person is 70, one should stand up. 
- There is a positive mitzvah Deoritta to stand for a Talmid Chacham who is more knowledgeable in Torah than most people and not simply a Yeshiva Bachur. (Standing for one's Rebbe Muvhak or a Gadol HaDor have separate halachot) 
- For an elder or Talmid Chacham, one should stand up completely, not just partially. One should stand from the time the elder or Talmid Chacham enters one's 4 amot until he passes from before one's face; some say that one should stand until the elder or Talmid Chacham leaves one's 4 amot. 
- According to Ashkenazic minhag, one has to stand for a particular Talmid Chacham or elder only once in the daytime and once at night unless one is in the presence of people who don’t know he stood previously; Sephardim, however, hold that one must stand up every time. 
- There are some who try to justify a minhag of being lenient regarding standing for an elder and Talmid Chacham. 
- Regarding standing for an elderly person or a talmid chacham in middle of pesukei dezimrah, see Pesukei_DeZimrah#Interruptions_in_middle_of_Pesukei_Dezimrah
- S”A YD 244:1 writes that it is a positive command to stand up for an elderly person of age 70. Kitzur S”A 144:2, Chaye Adam 69:2, and Aruch HaShulchan 244:1 agree. Birkei Yosef 244:4, however, quotes the Arizal who says that one should stand for a person of age 60. Sh”t Yabia Omer 3:13 and 9:13 writes that while the halacha follows S”A, one who is strict for the Arizal will be blessed.
- S”A 244:7 writes that for a non-Jewish elder one should speak respectfully and offer one’s hand to support him. Levush 244:7, Chaye Adam 69:2, and Kitzur S”A 144:2 agree. Kesef Mishna (Talmud Torah 6:9) writes explicitly that there is no mitzvah to stand for a non-Jewish elder. Therefore, Kavod VeHiddur (p. 78) rules that one does not have to stand for a non-Jewish elder at all.
- Yalkut Yosef YD 244:16 writes that if one isn't sure if the person is 70, he should stand up based on the principle of Safek Deoritta LeChumra. Tosefet Chaim on Chaye Adam 69:2, Shevet Halevi 5:130, Salmat Chaim YD 62, and Hiddur Panim (p. 109#14, citing Rav Elyashiv) agree. See, however, the Rogatchover’s comment on Salmat Chaim p. 58 who seems to say one is exempt.
- S”A 244:1 rules that it is a positive mitzvah to stand for a Talmid Chacham. Shach 244:2 explains that only a Talmid Chacham who is wiser than most people is considered a Talmid Chacham for this halacha. This is quoted by Baeir Heitev 244:2, Chaye Adam 69:1, and Aruch HaShulchan 244:4. Avnei Yashfeh 188:1 writes that certainly there is no obligation to stand for a yeshiva bachur. Yalkut Yosef YD 244:16 writes that one has to stand only for a Talmid Chacham who knows how to give psak in even haezer and choshen mishpat and not just someone learning in kollel.
- See S”A YD 244:10
- Tur 244, Taz 244:4, Gra 244:11, Chaye Adam 69:4, Kavod Vehiddur p. 64, and Sh”t Yabia Omer 3:13 write that one should stand completely for an elder just like one stands completely for a Talmid Chacham. This is in opposition to Aruch HaShulchan 244:10-2 who defends the minhag to stand partially for an elder. See also Teshuvot VeHanhagot YD 3:279 who is seems to agree.
- S”A 244:2 rules that one should stand once the Talmid Chacham or elder enter one's 4 amot. Shach 244:6 adds that it is forbidden to stand before a Talmid Chacham enters one's 4 amot because there is no presentation of respect by standing at that distance. Birkei Yosef 244:11 and Chaye Adam 69:3 agree. Kavod VeHiddur p. 63 writes that this applies equally to an elder and a Talmid Chacham. Sh”t Yabia Omer 4:16 agrees, rejecting the Ben Ish Chai Ki Teitzei 13 who says that once the elder enters the room, one should stand, as the whole room is considered like 4 amot. Kavod VeHiddur p. 63 quotes Hadar Zekenim (chap 1, note 15) that one doesn't need to measure 4 amot; it's enough to stand where it seems like 4 amot.
- S”A 244:2 and 9 says, based on Rambam, that one may sit after the elder or Talmid Chacham has passed from before one's face. Bach 244:5, based on Rashi, says that one should be strict to continue to stand until they leave his 4 amot. Shach 244:7, Aruch HaShulchan 244:13, and Hiddur Panim (p. 109 #16, quoting Rav Elyashiv) agree with the Bach. Chaye Adam 69:3 quotes S”A as the anonymous opinion and Bach as “some say.” Birkei Yosef 244:12 holds like S”A. Kavod VeHiddur (p. 65 note 69) writes that this applies equally to an elder and a Talmid Chacham.
- Rama 242:16 writes that one has to stand for one's Rebbe once in the morning and once at night unless one is in the presence of people who don’t know that he stood previously. Taz 242:12 explains that one shouldn't have to stand more often than one says Shema, which is an expression of respect for heaven. Shevet HaLevi 5:130 and Hiddur Panim (p. 109 #18) quoting Rav Elyashiv rule like the Rama. Kavod VeHiddur p. 67 quotes gedolei horaah who say that this applies equally to an elder and Talmid Chacham. However, Birkei Yosef 242:21 explains that S”A holds that one should stand every time. Rabbi Mansour on DailyHalacha.com (12/30/10) writes that Sephardim should follow Birkei Yosef.
- Shach 244:11 seems to say that the minhag is to stand only for an Av Bet Din or Rosh Yeshiva, but he leaves it as a tzarich iyun. Rav Chaim Zonenfeld in Salmat Chaim YD 59-60 explains that the Shach doesn't mean that they uprooted a Deoritta but rather that the Talmidei Chachamim forgo the respect due to them. Rabbi Zonenfeld seems to say that this is not accepted as the Halacha but only a defense of the minhag. Similarly, Sh”t Yabia Omer YD 3:13 writes that one should certainly not rely on the assumption that Talmidei Chachamim are mochel. Kavod VeHiddur p. 38 cites some who say that we assume that in general a Talmid Chacham is mochel. Rabbi Hershel Schachter (Halachipedia Article 5772 #15) stated that we assume a Talmid Chacham is mochel people standing for him.
- Regarding elders, Kavod VeHiddur p. 64 quotes Rav Elyashiv saying that the minhag has what to rely on, since we assume that elders forgo the respect due to them.