"کتب علیکم تجدید اسباب البیت بعد انقضاء تسع عشر سنه کذلک قضی الامر من لدن علیم خبیر"

“It is prescribed for you to renew your house furniture after passing 19 years. It is ordered by the aware God.[1]

However, it needs lots of money and the owner bears lots of difficulties. Although this commandment causes change in humane life; but it causes difficulty financially and spiritually and physically[2].

There hasn’t been such commandment in any heavenly world like this to investigate the details of life.