What is the evidence that the one who joins the prayer late is in the ruling of the one following the imam?

The questioner : The questioner : You mentioned that he is in the ruling of the one following the imam. What is the evidence?The Shaykh : Because he followed the imam.

The questioner : Even after the imam has said the closing salam, meaning?

The Shaykh : Yes.

The questioner : So, if someone passes in front of him, he does not break his prayer?The Shaykh : He does not break his prayer unless he is able to cover himself with the previously mentioned condition.

The questioner : Yes, may Allah bless you.