In the sMyo shul chos ’byung (p. 345), we find the following list: first, three disciples who were both learned and spiritually accomplished (mkhas grub): Khyab brdal lhun grub (the heir of the lineage), bDe legs rgya mtsho (who appears as Klong chen rab ’byams’ successor in the transmission of the Rang grol skor gsum, as we have seen above) and Chos kyi grags pa. Then five “heart-sons:” ’Dan sgom Chos grags bzang po (the biographer), rGyal sras bZod ba grags pa, Bla ma dPal mchog, Guru Ye shes rab ’byams and gZhon nu sangs rgyas. Then four masters who spread Klong chen rab ’byams’ teaching: sPrul sku dPal ’byor rgya mtsho, Slob dpon Sangs rgyas kun dga’, Slob dpon Blo gros bzang po and sTag mgo bya bral Chos rje bKra shis ’byung gnas. Then four yogin who attained spiritual attainments: Phag rgod rTogs ldan rgyal po, rNal ’byor ’Od zer go cha (the disciple who had brought to Klong chen rab ’byams the complete mKha’ ’gro snying thig corpus), Guru ’Od gsal rang grol and Bya btang Dam pa ’od zer.
sMyo shul mkhan po mentions also ’Khrul zhig Sangs rgyas dbon po, Grog O rgyan Chos rje, Glu mkhan Dam pa seng ge, Grags pa dpal and Sangs rgyas dpal rin. There is at least one other disciple whose presence is recurrent in the mThong snang rin po che ’od kyi dra ba: it is ’Od zer mtha’ yas. But perhaps this is another name (e.g., an empowerment name) of one of the previous disciples.
The Deb sngon (p. 722) also informs us that a certain Chos dbyings pa (1324-?), or Chos dbyings dbang phyug, “disciple of six direct disciples of Dung mtsho ras pa,” received teachings from a “rGyal sras Dri med pa” who is none other than Klong chen rab ’byams. This person seems to have discovered a gter chos related to the rubric of the mind (Sems sde) of the Great Completeness, which is both almost unique in itself and all the more astonishing in the fourteenth century, a time of hegemonic diffusion of the various forms of sNying thig.
The following is an abbreviated version of what can be learned from sMyo shul mkhan po’s Chos ’byung about Klong chen rab ’byams’ main direct disciples.
Khyab brdal lhun grub: His date of birth is not known. He was a fully consecrated monk, versed in both exoteric doctrines and the ancient and modern tantras. He was a disciple of the following masters (in order of appearance in the biography): Chos lung mkhan chen Dam pa grags pa (from whom he received full consecration [“ordination”] in his seventeenth year), rGyal sras Thogs med (1295-1367 according to Deb sngon or 1369 according to Bod rgya tshig mdzod chen mo); ’Jam dbyangs Legs ldan pa (Sa skya pa master); Bla ma Kun rin [could this be sGom chen Kun rin ?]; rDo rje gling pa (1323-?); Rin chen gling pa (1274?-1353?); Ye shes rgyal po (rnying ma pa). He was appointed abbot of Lha lung Jo gdan sde (stan gcig pa monastery, i.e., ldan gcig pa, of strict observance, known from Guru bKra shis) at the instigation of Chos lung mkhan chen Dam pa grags pa and seems not to have failed to live up to the trust placed in him. He met Klong chen rab ’byams while the latter was en route to Bhutan. According to my supposition – that not of an abrupt exile in Bhutan in 1354 or 1359, but of occasional stays in this country from about 1350 – this only allows us to place this meeting in a very broad range, between 1350 and 1364. In any case, after receiving teachings from the master of Gangs ri thod dkar, Khyab brdal lhun grub built a hermitage and withdrew there to meditate for five years. He was then the principal of those who brought Klong chen rab ’byams back to lHo brag. He later received Klong chen rab ’byams’ teaching again, especially on the mKha’ ’gro snying thig, and revised his understanding with him. Klong chen rab ’byams thought highly of him, made him the heir to his doctrine and entrusted him with the task of passing it on to his son, sPrul sku Grags pa ’od zer. He died in his ninety-seventh year.
Assuming with Tülku Thondup that Grags pa ’od zer was born in 1356, knowing that, according to sMyo shul mkhan po (op. cit., I, p. 354), it was in his fifth year (1360) that he was entrusted to Khyab brdal lhun grub, one can propose the following hypotheses : 1360, return of Klong chen rab ’byams to Tibet (at least to lHo brag); 1355 at the latest : meeting with Khyab brdal lhun grub, since between the two meetings, the latter spent five years in retreat. I think that this confirms the date given by Samten Karmay for the exile of Klong chen rab ’byams in Bhutan (1354) and invalidates Guenther’s suggestion (1359).
Khyab brdal lhun grub had as main disciples, besides Grags pa ’od zer, the gter ston rDor je gling pa (they were thus reciprocally master and disciple), Bya btang rGyal mtshan grags, Guru Don yod pa, rTogs ldan Ye shes dpal ba and Tshul khrims rgyal mtshan.
Khrul zhig Sangs rgyas dbon po: he comes third after Khyab brdal lhun grub and Grags pa ’od zer in the lineage of sNying thig after Klong chen rab ’byams. The succession of masters must have been very quick, for Sangs rgyas dbon po is obviously almost of Klong chen rab ’byams’ generation of, since he was a disciple of the third Karma pa, Bu ston and “rGyal sras pa,” i.e. rGyal sras Legs pa. Bu ston died only in 1364, but the Karma pa had died in 1339. Therefore, Sangs rgyas dbon po must have been born in the early fourteenth century. He also studied under Dam pa bSod nams rgyal mtshan, Chos lung mkhan chen Dam pa grags pa, whom we have just met, and Paṇ chen Phyogs las rnam rgyal of Jo nang, etc. (in all “more than fifty masters,” according to Guru bKra shis ).
He was consecrated [“ordained”] in his eighteenth year by Dam pa bSod nams rgyal mtshan. Knowing that the latter was born in 1312, Sangs rgyas dbon po can hardly be born before 1315 or even 1320.
He met Klong chen rab ’byams “on his return from Bhutan” (Chos rje kun mkhyen chen po lho mon nas phyir phebs pa gzhung gi ri bor bzhugs pa’i drung du mjal, op. cit. p. 359), then a second time “when the Great Omniscient, who was in ’Bri gung, had responded to [an] invitation and was giving in mChims phu the sNying thig empowerments and instructions”. The master “passed away when he reached the end of [the part of the teaching] devoted to the path of Khregs chod”. These two encounters could be dated to 1360 or 1361 for the first and – obviously – 1364 for the second. He then devoted himself entirely to meditative practice.
The biography mentions again, after the episode of Klong chen rab ’byams’ death, his accointances with “Paṇ chen pa,” i.e. Phyogs las rnam rgyal of Jo nang, and with an O rgyan pa – who obviously cannot be the one who was the master of the third Karma pa, but rather must be the personage we are dealing with below. He seems to have combined ancient and modern tantra practices for several years and then returned to the sNying thig in stages, first receiving teachings and empowerments from Gu ru ba Grags pa mtshungs med ’od gsal rang grol, with whom he studied and meditated for six years, before meeting Grags pa ’od zer, Klong chen rab ’byams’ son, whose teachings of the two sNying thig seem to have satisfied him perfectly.
It is not known at what age he died, but it is clear that Klong chen rab ’byams, Khyab brdal lhun grub, Grags pa ’od zer and ’Khrul zhig Sangs rgyas dbon po do not belong to four successive generations: the first two are roughly of the same generation, the fourth is of the next generation, and the third could have been the son of his disciple (which, after all, is not very surprising judging from the current situation among Tibetans). Assuming that Sangs rgyas dbon po met Rang byung rdo rje as a child, let us assume that he must have been born around 1330; he would have been between 30 and 35 years old at the time of his two encounters with Klong chen rab ’byams; and then he would have studied with Grags pa ’od zer, let us assume, when the latter would have been about 25 years old, while Sangs rgyas dbon po would have been in his fifties (about 1381). However, there is no evidence that he survived Grags pa ’od zer (who died in 1409), or even Khyab brdal lhun grub, who must have died in the last years of the fourteenth century.
Bla ma O rgyan pa: a short biographical note (op. cit., II, pp. 83-87) is devoted to this figure by sMyo shul mkhan po; some elements are also found in Guru bKra shis (op. cit., p. 231). Nothing is known of his family or his youth, except that he was a ’Bri gung pa monk, trained in philosophy at gSang phu; he seems to have played a role in the invitation of Klong chen rab ’byams to ’Bri gung, and then to have made an offering of materials for the restoration of the Zhwa’i lha khang (1349). It was he who gave Grog O rgyan dgon to Klong chen rab ’byams (but this contradicts the idea that it was sGom pa Kun rin who gave him this gift; the two men must have been in a feudal subordination relationship of the first to the second, which makes a gift from the vassal as well as a gift from the suzerain), who instituted him as bla ma of the latter monastery and of rGya ma gnas. Guru bKra shis assumes a connection between the political catastrophe of sGom pa Kun rin and Bla ma O rgyan pa’s engagement in the practice of rDzogs chen. He is said to have invited Klong chen rab ’byams to Yar ’brog after his return from exile (c. 1360-1361). After Klong chen rab 'byams’ death, he is said to have maintained and spread his teaching, notably by training one of Klong chen rab ’byams nephews, Sangs dbon Shes rab rgya mtsho. sMyo shul mkhan po indicates (p. 86) that the Lhun grub gling (often mentioned in the colophons of Klong chen rab ’byams’ works) is in fact Grog O rgyan dgon. A rather obscure remark by sMyo shul mkhan po (p. 87) seems to sketch out a connection of Bla ma O rgyan pa’s activity with ’Bri gung dPal ’dzin’s anti rnying ma pa polemic. The parallel passage is somewhat clearer in Guru bKra shis. Perhaps it is an allusive indication of an assumption by sMyo shul mkhan po about the authorship of a text dubiously attributed to Klong chen rab ’byams which I elsewhere menioned as the Triumph Over Error, the sNga ’gyur rnying ma la rgol ngan log rtog bzlog pa’i bstan bcos.
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 Perhaps Grags pa ’od zer, Klong chen rab ’byams’ son. To be compared with Chos kyi grags pa (Blue Annals, p. 724) who is said to have inherited from Chos dbyings pa (himself a disciple of Klong chen rab ’byams, ibid, p. 723) the Yang ti nag po which the latter had from six direct disciples of gter ston Dung mtsho ras pa (p. 722 ff.).
 Probably also a direct disciple of rGyal sras Legs pa, the disciple of Padma las ’brel rtsal. Cf. this passage from the biography of Zla ba grags pa, the grandson of Klong chen rab ’byams (op. cit., I, p. 364): Shug gseb pa Ye shes rab ’byams las mKha’ ’gro snying thig gter ston Padma las ’brel rang nas | rGyal sras Legs ldan par brgyud pa yang gsan te |... Guru bKra shis’ Chos ’byung (p. 224) confirms that the disciple of Klong chen rab ’byams is indeed Shug gseb pa Ye shes rab ’byams.
 His main source seems to us to be the Chos ’byung of Guru bKra shis (ed. cit., p. 224 ff.). It is interesting and curious that he changes the order of the text, for a reason that escapes me.
 It might be more reasonable to assume that a list of successive patriarchs was made up after the fact, using the names of several of Klong chen pa's principal direct disciples as if they had been teachers and disciples of each other.
 Op. cit. , p. 234.
 Op. cit. p. 360: De’i tshe kun mkhyen chen po ’Bri gung du bzhugs pa spyan ’dren du byon nas mChims phur sNying thig gi dbang khrid gsungs pa....
 Op. cit. same page: Khregs chod kyi lam rDzogs pa’i mtshams su zhi bar gshegs pa...
 Op. cit. (p. 231): ’Bri gung sGom pa Kun rin srid sde skyong ba’i dmag ’khrug gi sdig g.yos la yid phyungs te dam pa’i chos la rigs sad rDzogs pa chen po’i lam zab la mos shing dungs pas...
 Op. cit. p. 232: Kun mkhyen chen po sku gshegs pa'i rjes su | bla ma 'dis Grogs O rgyan sogs su Kun mkhyen chen po'i bka' srol rDzogs pa chen po'i 'khor bstar chags su bskyangs pa las skal ldan gyi slob ma 'du ba rgya cher byung ba'i phun sum tshogs ma bzod pas E-waṃ dang Thang skya'i bla ma 'Bri gung dPal 'dzin du grags pa rDzogs chen gtsor smos pa'i rnying ma la chos spong gi sgrib pa'i khur bzod dka' ba yang blangs so | zhes gTer bdag gling pas gsungs so |