Is it correct for one not to perform any established act of worship from the Messenger (peace and blessings of Allah be upon him) until they understand its benefit? And did the Companions perform what came to them from revelation regarding acts of worship without questioning? What are some examples of that?

The Muslim's submission to the command of Allah and His Messenger should not depend on knowing the wisdom behind the legislation, because we are servants of Allah and human intellects are limited in grasping His wisdom. The duty is to promptly comply with the command of Allah Almighty, for Allah is Wise and legislates only for a benefit, whether it is apparent to the servant or hidden. Allah Almighty has praised the believers for their promptness in hearing and obeying His commands, as in His saying: "We hear and we obey," and "they will not believe until they make you judge in what they differ, and then find no discomfort in their souls concerning what you have decided and submit in full submission." The lives of the Companions were a living example of this character, as they would promptly comply with Allah's command without questioning or debating, such as when they overturned their pots of domestic donkey meat on the day of Khaybar, and when they poured out wine immediately upon its prohibition. Muslims should emulate the Companions in their submission to the commands of the Sharia and their prompt acceptance of their Lord's judgment without hesitation.