Keilim 25:8-9

Keilim 25:8

Continuing from the previous mishna, if one’s hands were ritually clean and the exterior of a cup was ritually unclean, then if one held it by the finger holds, he need not be concerned about his hands contracting impurity from the cup’s exterior. If one was drinking from a cup whose exterior was unclean, he need not be concerned about the liquid in his mouth contracting impurity from the exterior of the cup and then conveying impurity to the cup(‘s interior). If a kettle is boiling, one need not be concerned about the possibility that liquid might come out, touch the (impure) exterior and return to the interior.

Keilim 25:9

Sacred utensils do not have different rules for their outsides, insides and finger holds. We are not permitted to immerse utensils inside of other utensils for use with sacrificial food. All utensils become susceptible to ritual impurity through one’s intention but they can only be rendered insusceptible to impurity by physically altering them. This is because one’s actions can cancel his previous actions and intentions but one’s intentions cannot cancel his previous actions or intentions.