Liturgy for Shevuot 98:14

גופא אמר ר' אמי כל שבועה שהדיינין משביעין אותה אין בה משום שבועת ביטוי שנאמר (ויקרא ה, ד) או נפש כי תשבע לבטא בשפתים מעצמו כדר"ל דאמר ר"ל כי משתמש בארבע לשונות אי דלמא אלא דהא

In what do they disagree? - Samuel holds it is not [possible of application] in the future;<span class="x" onmousemove="('comment',' He holds that a sliding-scale sacrifice for a false oath of utterance is brought only if that oath is applicable to the future; e.g., if the guardian swore falsely, 'The animal died,' he does not bring a sliding scale sacrifice, for he could not swear, 'The animal will die'; v. supra 25a.');">¹⁵</span> and Rab holds it is [possible of application] both negatively and positively.<span class="x" onmousemove="('comment',' Applicability in the future is not necessary, as long as it is applicable in the negative and positive; e.g., the animal died, or did not die; was stolen, or was not stolen.');">¹⁶</span>

Hadran