If the mortgagee's word is accepted, is he required to swear an oath?

Primary text

If the mortgagee's word is accepted, he must swear an oath in all circumstances because his admission would establish a right in the mortgage. His oath is one of absence of knowledge, as it concerns the actions of others. If he swears, the claim against him is dismissed, but the effect of the mortgagor's prior admission remains tied to the property, meaning if the mortgage ever reverts to the mortgagor, the effect of his admission will manifest.