Batsman De Villiers has not played Test cricket since January 2016 while fast bowler Steyn suffered a fractured shoulder in a Test against Australia in November 2016 and only returned to competitive cricket last month.
New ball bowler Vernon Philander is also back after missing a recent series against Bangladesh because of a back injury.
South Africa’s top four fast bowlers are reunited, with Morne Morkel having recovered from an injury he suffered during the first Test against Bangladesh.
“AB and Dale bring loads of experience to the side apart from being two of the South African all-time greats,” said selection convener Linda Zondi.
Faf du Plessis was named as captain, although he has been out of action recently following a shoulder operation.
Although De Villiers is set to return to Test action, he was withdrawn from the South African Invitation team which starts a three-day match against the Zimbabweans in Paarl on Wednesday because of lower back stiffness.
Zondi said the withdrawal was a precaution and that De Villiers would be available for the Test.
South African Test squad
Faf du Plessis (captain), Hashim Amla, Temba Bavuma, Quinton de Kock (wkt), Theunis de Bruyn, AB de Villiers, Dean Elgar, Keshav Maharaj, Aiden Markram, Morne Morkel, Andile Phehlukwayo, Vernon Philander, Kagiso Rabada, Dale Steyn.
— Cricket South Africa (@OfficialCSA) December 19, 2017
The Kiwi has already played alongside the Pakistan man in the Caribbean Premier League (CPL) earlier this year.
The rising teen sensation from Pakistan is set to make his debut for the Heat on Wednesday’s tournament opener against the Melbourne Stars at the Gabba.
McCullum was speaking to the press after signing a two-year contract extension with the Brisbane based team.
“I’m very excited about Shadab. I played with him (in the CPL) and followed his career around the globe.
‘‘He’s only a young man but he’s already made a big impact on world cricket. He is a multi-skilled cricketer. He is dynamic in the field and has been brilliant with the bat in hand.
“I’m sure the Brisbane public will warm to him,” the former Blackcaps man said.
The 19-year-old for his part was delighted to be a part of the Australian T20 competition for the coming season and recognized the fact that he will not get much assistance in the pitches on offer.
“Last year I saw the Big Bash on the TV and now I’m playing,” he said.
“I’ll play the first three games and I want to be the best bowler in those games. I’ve seen on TV that Australia doesn’t spin too much so I’ll do my best to bowl variations to contain runs and take wickets,” he added.
The leg-spinner has risen to prominence this year after his introduction at the international stage with some promising displays in limited-overs cricket. He was an integral part of the ICC Champions Trophy winning Pakistan side earlier this summer.
Australia regained the urn after an innings-and-41-run victory over England in the third Test at Perth, moving into an unassailable 3-0 lead in the five-match series.
England will now seek to avoid a third series whitewash in Australia in their past four trips and Ashes 2005 winning captain Vaughan has called on the tourists to leave Moeen out of their plans for the Boxing Day Test at Melbourne.
The all-rounder has taken just three wickets – although he has been hampered by a finger injury – and has also flattered to deceive with the bat, with 116 runs at an average of 19.33.
He is below Australia’s number nine Pat Cummins in the run-charts while he has been dismissed in five of his six innings by opposite number Nathan Lyon, who has been one of Australia’s pivotal performers so far.
Vaughan said on BT Sport 1: “You’ve got to make the change. If Moeen Ali’s going to be the batsman that just bowls a little bit then he’s got to bat a bit better than we’ve seen already.
“For me, Moeen Ali can’t play in Melbourne.”
Former England batsman Geoffrey Boycott bemoaned the gulf in class between Moeen and Lyon.
The pundit said: “It’s not a contest. My mum could play Moeen.
“We play a batsman who can bowl a bit. He’s done quite well for us, Moeen Ali, but he’s not a quality spinner. He’s nothing like a quality spinner.”
Boycott, who featured in 108 Tests between 1964 and 1982, also highlighted the lack of credible genuine fast bowlers that could rival Mitchell Starc or Cummins for pace.
He added: “They need to get better players and they haven’t got better players in English cricket. English cricket has a paucity of quality.
“Every member or supporter of their county club will tell you somebody who they would have picked instead of one or two in this team, but you can’t honestly say at home there are players who ought to be in this side.”
With a series defeat now confirmed, Vaughan believes captain Joe Root needs to start thinking of the long-term for the Tests in Melbourne and Sydney.
He added: “Joe Root needs to take out 10 players out with him that are desperate to be out there in in the middle at the MCG.
“He’s 10 games into his role. He’s got to start having a look around the dressing room and try and identify the characters that he wants to take forward, there might be one or two that he doesn’t.
“Over the next few weeks he’s got to try to have a look around the team.
“Is it now time to start building? Is it now time to start looking at the future? And if it means that he has to make a tough call or two then he’s going to have make that.”