Responsa for Nedarim 60:2
ומאן דמתני אסיפא מתני הכי הנודר מיושבי יבשה אסור ביורדי הים ולא באלו ההולכים מעכו ליפו בלבד אלא אפילו במי שדרכו לפרש הואיל וסופו ליבשה סליק
<b><i>MISHNAH</i></b>. HE WHO VOWS [NOT TO BENEFIT] FROM THE SEERS OF THE SUN, IS FORBIDDEN FROM THE BLIND TOO, BECAUSE HE MEANT THOSE WHOM THE SUN SEES'.<span class="x" onmousemove="('comment',' [I.e.. he might have intended the phrase 'those who see the sun' as an euphemism for 'those whom the sun sees', i.e., the blind (cf. Bek. VIII, 3, [H], 'looking to the sun' used euphemistically for 'squinting'). But since with vows we adopt the more rigorous interpretation, he is forbidden to benefit from those who see as well as from the blind (cf. Rabinowitz, M. Graber Otzar ha-Safruth II, 137ff.).] ');"><sup>1</sup></span>
Teshuvot Maharam
A. Vows are interpreted according to common parlance. If the phrase "I will not gamble again" includes, in common parlance, gambling by proxy, he must pay the fine. If, however, the implications of the phrase in common speech can not be determined, we must follow Biblical use of terms. In Biblical law a person is responsible for the acts of his agent unless the agent himself commits a sin by carrying out his mission. Although A's vow was made in the form of Asmakta, it is binding since all promises to a holy cause, even when made in the form of Asmakta, are binding.
SOURCES: Cr. 299, 300; Pr. 493, 494; L. 211, 212; Mordecai Hagadol p. 337b. Cf. Asher, Responsa 13, 2; Agudah B.K. 51.