Is buying necessities during congregational prayer time—which leads to missing it—permissible or forbidden?

Attending congregational prayer in the mosque is obligatory for the able-bodied man who hears the call to prayer (adhan). It is not permissible to abstain from it except for a valid, recognized legal excuse. This is based on what has been narrated from the Prophet, peace and blessings be upon him, concerning warnings against those who abstain from it, such as his saying: "By Him in Whose Hand is my soul, I was about to order for firewood to be collected, then order for the adhan to be called, then order a man to lead the people in prayer, then go to men [who did not attend] and burn their houses down on them." This opinion has been favored by a group of scholars, such as Ibn al-Mundhir, Ibn al-Qayyim, and the two Sheikhs, Ibn Baz and Ibn Uthaymeen. Therefore, abstaining from congregational prayer without an excuse, such as being preoccupied with shopping and buying, is forbidden and requires repentance.