Is it permissible to abandon growing the beard, raising the izar, and congregational prayers for fear of pursuit and imprisonment, or is it obligatory to adhere to them?

"When trials occur, people are divided into those who succeed and those who fail. Tribulation is a universal law to distinguish the truthful. A Muslim must persevere in obedience to Allah, and the objections of people should not be an obstacle, for the reward is greater for performing acts of obedience during times of tribulation, as confirmed by the words of the Prophet, peace and blessings be upon him: "Worship during times of widespread chaos is like emigration to me," and "A time will come upon people when the one who adheres steadfastly to his religion will be like one grasping a burning coal." Satan's intimidation with punishments is part of his cunning, so a Muslim should fear no one but Allah and adhere to the religious commands. Whoever fears Allah, He will provide a way out for him. One should not care about people's opinions, for most of them are astray, unless an act of obedience entails a confirmed punishment like imprisonment, for necessities permit forbidden things."