Here "bind heavy burdens" is a metaphor for the religious leaders making many rules that are difficult for people to obey. AT: "they make you obey many rules that are difficult to follow ... do anything to help you follow them" (See: [[rc://en/ta/man/translate/figs-metaphor]])
Here "move a finger" is a metaphor for giving help. AT: "they will not give the least amount of help" (See: [[rc://en/ta/man/translate/figs-metaphor]])
This can be stated in active form. AT: "They do all their deeds so that people can see what they do" (See: [[rc://en/ta/man/translate/figs-activepassive]])