To what extent is the hadith sound: "It is close that stones will rain down upon you from the sky; I say to you, 'The Messenger of Allah said,' and you say, 'Abu Bakr and Umar said'"? And what is its meaning, and how does it apply to the present time?

This report about Ibn Abbas is sound in its meaning: that the saying of the Prophet, peace and blessings be upon him, takes precedence over the saying of anyone else, whether from the Companions or others. It is not permissible to contradict his Sunnah with anyone's saying or action.

Ibn Abbas substantiated his argument with the Prophet's hadith regarding mut'ah (temporary marriage), while Urwah opposed him with the saying of Abu Bakr and Umar. Ibn Abbas then emphasized the obligation of following what came from the Prophet, peace and blessings be upon him.

This meaning necessitates that a scholar and a qualified student of knowledge prioritize the legal evidence over anyone's statement. As for the common person, their obligation is to ask the people of knowledge and follow their fatwas.