What is the decree on raising the hands while starting a prayer, bowing down for ruku’ and before prostration according to Shafii madhhab?

What is the decree on raising the hands in prayer? Does it cause any negativity if a person does not raise his hands while starting a prayer, bowing down for ruku’ and before prostration? What will be the degree of validity of the prayer?

Dear Brother / Sister,

It is sunnah to raise hands while uttering takbir while starting a prayer, bowing down for ruku’ and standing up from ruku’.  

This sunnah is fulfilled as follows: 

The palms of the hands are opened and they face the qiblah; the fingers are kept separate. The thumbs are at the level of the earlobes and the palms are open. (It is mustahab for the palms to face the qiblah at that time.)

Ibn Umar narrates the following:

'When Hz. Prophet started a prayer, he would raise his hands up to the level of his shoulders and utter takbir. When he wanted to bow down for ruku’ and stand up from ruku’, he did the same thing. However, he did not do so when he prostrated and when he sat up after prostration.' (Büyük Şafii Fıkhı, Dr. Mustafa al-Hin, Dr. Mustafa el-Bugha, Ali ash-Sharbaji, Translated by Ali Arslan)

Accordingly, every Shafii person, whether he is the imam, follows the imam or performs a prayer alone, whether a woman or a man, raises his/her hands up to the level of the shoulders when he/she starts a prayer, bows down for ruku’ and stands up from ruku’. (al-Umm, raful-yadayn fit-takbir: 1/103, 104)

However, this takbir is among hay'at sunnahs. When they are abandoned, sajdah as-sahw is not necessary; the prayer is valid. However, a sunnah is abandoned.

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