Like the Hippocratic oath for medical practitioners, this should become the oath for all inquirers. Veda is inquiry. Not a myth. So, add an explanatory phrase: do not try to trace origins of myths with non-falsifiable methods and evil intent to break the imperative of abhyudayam. Dharmam-Dhammam cara -- do your duty -- for attainment of abhyudayam.
वेदमनूच्याचार्योऽन्तेवासिनमनुशास्ति
सत्यं वद, धर्मं चर, स्वाध्यायान्मा प्रसदः
आचार्याय प्रियं धनमाहृत्य प्रजतन्तुं मा व्यवच्छेत्सीः
सत्यान्न प्रमदितव्यम्, धर्मान्न प्रमदितव्यम्
कुशलान्न प्रमादितव्यम्, भूत्यै न प्रमादितव्यम्
स्वाध्यायप्रवचनाभ्यां न प्रमदितव्यम् ॥ १ ॥
देवापितृकार्याभ्यां न प्रमदितव्यम्
मातृदेवो भव, पितृदेवो भव
आचार्यदेवो भव, अतिथिदेवो भव ॥ २ ॥
यान्यनवद्यानि कर्माणि, तानि सेवितव्यानि
नो इतराणि, यान्यस्माकगं सुचरितानि
तानि त्वयोपास्यानि, नो इतराणि ॥ ३ ॥
ये के चास्मच्छ्रेयाणो ब्राह्मणाः
तेषां त्वयाऽऽसनेन प्रश्वसितव्यम् ॥ ४ ॥
श्रद्धया देयम्, अश्रद्धयादेयम्
श्रिया देयम्, ह्रिया देयम्
भिया देयम्, संविदा देयम् ॥ ५ ॥
अथ यदि ते कर्मविचिकित्सा वा वृत्तविचिकित्सा वा स्यात्
ये तत्र ब्राह्मणाः सम्मर्शिनः, युक्ताः आयुक्ताः
अलूक्षा धर्मकामाः स्युः, यथा ते तत्र वर्तेरन्
तथा तत्र वर्तेथाः ॥ ६ ॥
अथाभ्याख्व्यातेषु, ये तत्र ब्रह्मणाः सम्मर्शिनः
युक्ताः आयुक्ताः, अलूक्षा धर्मकामाः स्युः
यथा ते तेषु वर्तेरन्, तथा तेषु वर्थेथाः ॥ ७ ॥
एष आदेशः, एष उपदेशः, एषा वेदोपनिषत्
एतदनुशासनम्, एवमुपासितव्यम्
एवसु चैतदुपास्यम् ॥ ८ ॥
vedamanuuchyaachaaryo.antevaasinamanushaasti
satya.n vada, dharma.n chara, svaadhyaayaanmaa prasadaH
aachaaryaaya priya.n dhanamaahRRitya prajatantu.n maa vyavachchhetsiiH
satyaanna pramaditavyam, dharmaanna pramaditavyam
kushalaanna pramaaditavyam, bhuutyai na pramaaditavyam
svaadhyaayapravachanaabhyaa.n na pramaditavyam (1)
devaapitRRikaaryaabhyaa.n na pramaditavyam
maatRRidevo bhava, pitRRidevo bhava
aachaaryadevo bhava, atithidevo bhava (2)
yaanyanavadyaani karmaaNi, taani sevitavyaani
no itaraaNi, yaanyasmaakag.n sucharitaani
taani tvayopaasyaani, no itaraaNi (3)
ye ke chaasmachchhreyaaN^so braahmaNaaH
teShaa.n tvayaa.a.asanena prashvasitavyam (4).
shraddhayaa deyam, ashraddhayaadeyam
shriyaa deyam, hriyaa deyam
bhiyaa deyam, sa.nvidaa deyam (5)
atha yadi te karmavichikitsaa vaa vRRittavichikitsaa vaa syaat
ye tatra braahmaNaaH sammarshinaH, yuktaaH aayuktaaH
aluukshaa dharmakaamaaH syuH, yathaa te tatra varteran
tathaa tatra vartethaaH (6)
athaabhyaakhvyaateShu, ye tatra brahmaNaaH sammarshinaH
yuktaaH aayuktaaH, aluukshaa dharmakaamaaH syuH
yathaa te teShu varteran, tathaa teShu varthethaaH (7)
eSha aadeshaH, eSha upadeshaH, eShaa vedopaniShat
etadanushaasanam, evamupaasitavyam
evasu chaitadupaasyam (8)
Always speak the truth, do your duty, never swerve from the study of the Veda-s, do not discontinue your family's line of descendants, after giving the perceptor the fee he desires; never deviate from truth, never fail to perform your duty, never overlook your own welfare, never neglect your prosperity, never neglect the study and the propagation of the Veda-s (1). Never swerve from your duties towards Gods and towards the departed souls; may your mother be a God to you, may your father be a God to you, may your perceptor be a God to you, may your guest be a God to you (2). Let only those actions be done which are free from blemishes, and not others; may you follow only those virtuous which are blameless, and not others (3). May you offer seat to superiors and worship them with acts of respect and love (4). Gifts should be given with faith and never without faith; it should be given in plenty, with modesty and sympathy; while offering gifts, let there be feelings of affection (5). In case of any doubt regarding your acts or conduct in life, you should act exactly as those brahmana-s who are thoughtful, experienced, not influenced by others, not cruel, and are devoted to righteousness (6). With regard to those who are falsely accused of some crime, you should rule yourself exactly as those brahmana-s who are thoughtful, experienced, not influenced by others, not cruel, and are devoted to righteousness (7). This is the command, the teaching, the secret of the Veda-s, the commandment; and this should be observed. Having understood this fully, one must act accordingly, till the last (8).
[ This is the essence of Veda-s that the perceptor enjoins the disciples. (तैत्तरीय उपनिषद् - taittariiya upaniShad, यजुर्वेद - yajurveda) ]
http://samskrutam.com/samskrit/sanskrit-texts/upanishat-mantra.aspx