What is the ruling on telling a procrastinating debtor, "I want the money to be a debt on his conscience"? And does the debt of the procrastinator fall if someone pays half of the amount on his behalf?

The creditor's statement to the debtor, "I want the amount to be a debt on his neck," is not a waiver of the debt; rather, it is an affirmation of it and a warning to the debtor. If someone other than the debtor voluntarily pays part of the debt, only that part is discharged. The debt remains incumbent upon the debtor and is not cleared except by performance or discharge. So, if the debtor, his representative, or his guarantor pays the debt, or if the creditor wholly or partially discharges him, his liability is cleared to the extent of what was paid or discharged.