Does the prayer become invalid if one intentionally omits the prostration for forgetfulness?
Machine translationRead the Arabic original
The questioner : Yes.
The Shaykh : He says it is not dropped, and the school of thought says it is dropped, and the most likely view is that it is dropped.
The questioner : It is from the sky.
The Shaykh : No, no, I do not have the prayer; the prayer does not enter with it.
The questioner : It happened.
The Shaykh : Unless one intentionally omits the prostration for forgetfulness that comes before the closing salam, if he intentionally omits it.
The Shaykh : He says it is not dropped, and the school of thought says it is dropped, and the most likely view is that it is dropped.
The questioner : It is from the sky.
The Shaykh : No, no, I do not have the prayer; the prayer does not enter with it.
The questioner : It happened.
The Shaykh : Unless one intentionally omits the prostration for forgetfulness that comes before the closing salam, if he intentionally omits it.
Source
قناة «فضيلة الشيخ محمد بن صالح العثيمين»، 1134 - هل تبطل الصلاة إذا تعمد ترك سجود السهو؟ الكافي في فقه الإمام أحمد بن حنبل - ابن عثيمين — youtube.com
The Arabic text is a machine transcription of the audio recording.