2,765. "This" vs. "My"

Hilchos Nedarim 5:5

If person A tells person B, “This produce is prohibited to you,” but he doesn’t indicate “my produce,” then it remains prohibited to person B even if person A sold the produce, or he died and the produce was inherited by a third party. This is because when someone renders his property prohibited to another person, it remains prohibited unless he specifies “my property,” “my house,” “my produce,” etc. In such cases, person A only prohibits things while they are his.

Hilchos Nedarim 5:6

If a man tells his son, "You are prohibited to benefit from me,” or if he makes an oath prohibiting his son to benefit from him, the son may inherit his property when he dies. That’s because this is tantamount to saying, “My property is prohibited to you.” If he prohibited his son to benefit from him both during his lifetime and after his death, then his son does not inherit him because this is tantamount to saying, “This property is prohibited to you.”