Atharvaveda 11.3.49

11.3.49

[4.18]a) tátaś cainam anyáyā pratiṣṭháyā prā́śīr yáyā caitáṃ pū́rva ŕ̥ṣayaḥ prā́śnan |
[4.18]b) apratiṣṭhānò 'nāyatanó mariṣyasī́ty enam āha |
[4.18]c) táṃ vā́ aháṃ nā́rvā́ñcaṃ ná párāñcaṃ ná pratyáñcam |
[4.18]d) satyé pratiṣṭhā́ya |
[4.18]e) táyainaṃ prā́śiṣaṃ táyainam ajīgamam |
[4.18]f) eṣá vā́ odanáḥ sárvāṅgaḥ sárvaparuḥ sárvatanūḥ |
[4.18]g) sárvāṅga evá sárvaparuḥ sárvatanūḥ sáṃ bhavati yá eváṃ véda ||49|| [18]

If thou hast eaten it with another firm standing (pratiṣṭhā́) than that with which the ancient seers ate this, without firm standing, without support (āyátana) wilt thou die: thus one says to him; it verily [have] I not [eaten] coming hither, nor retiring, nor coming on; standing firm in truth, therewith have I etc. etc.