Short answers, pulled from the story.
Astronauts Bill Anders, Jim Lovell, and Frank Borman read from the Book of Genesis as Apollo 8 orbited the Moon. This event triggered a lawsuit by Madalyn Murray O'Hair alleging government endorsement of religion in violation of the First Amendment. The case was dismissed but established that religious observance in space would remain a contentious issue.
Buzz Aldrin performed a private communion service for himself using a kit provided by his church while on the lunar surface. He informed flight director Chris Kraft of his plans but chose not to broadcast the service at the request of Deke Slayton due to controversy over Apollo 8's reading. A microfilm Bible brought to the Moon by Ed Mitchell was later auctioned off in 2011.
NASA astronaut Michael S. Hopkins took six consecrated hosts to the International Space Station in September 2013. This allowed him to receive the Eucharist weekly during his 24-week mission. Three Catholic astronauts had previously received Holy Communion on the 17th of April 1994 during Space Shuttle mission STS-59.
Russian Orthodox Christmas was celebrated on the International Space Station on the 7th of January 2011. Cosmonaut Aleksandr Viktorenko initiated the crew blessing tradition when he requested one for the launch of Soyuz TM-20 in 1994. The whole crew also celebrated on December 25 two weeks prior.
In February 2014 the General Authority of Islamic Affairs and Endowment from Saudi Arabia issued a fatwa forbidding devout Muslims from participating as crew members in Mars One's proposed one-way mission to Mars. Farooq Hamada explained that protecting life against all possible dangers is an issue agreed upon by all religions. The National Fatwa Council had previously created guidelines for Muslim Obligations in the International Space Station in 2007.