Commentary for Kiddushin 45:7

אמר אביי לעולם שלא מדעתו ושאני כסף הואיל וקני ליה בעל כורחיה מקני ליה בעל כורחיה

And should you answer, what is meant by THROUGH HIS OWN AGENCY? Through his own agency too, and we are thus informed that his deed [of emancipation] and his hand [i.e., the right to acquire for himself] come simultaneously<span class="x" onmousemove="('comment',' In the very moment of taking the deed he is free, and hence can accept it on his own behalf. Otherwise, his acceptance would be just as though his master held it, and he would not be free.');">⁷</span>

Daf Shevui to Kiddushin