South Africa were 140 for two in reply to Australia's first innings of 369 when bad light ended play 8.4 overs early.
Kallis was 72 not out with AB de Villiers on 48 in an unbroken stand of 130 that started after South Africa had been reduced to 10 for two.
''As long as he's there there's a certain calmness in the dressing room,'' Arthur told a news conference.
''I think AB gleaned a lot from him today.
''A lot of people talk about how batting with Jacques calms them, and I think we saw that to a certain extent.
''Jacques is the key, and I know he badly wants a double hundred and let's hope it comes tomorrow.'' Arthur laid out South Africa's short-term game plan for tomorrow.
''We've got to get stuck in during the first session,'' he said.
''The wicket always does a bit after it's been under the covers. We need to negotiate that, and then we can have a look.'' Michael Hussey scored 75 to marshal Australia's middle order brilliantly.
''It was a very rewarding innings,'' Hussey told a news conference.
''I think between the last three wickets we got another 90 or 100 runs or so, so it was a good effort because we had to work pretty hard throughout the whole innings for all our runs.
''To get that extra hundred, we thought we had a very good score.'' Hussey said the Australians felt they had a slight edge going into the third day's play tomorrow.
''It's pretty evenly poised, although we've probably got our noses in front,'' Hussey said.
''If we can break this partnership we have a really good chance of rattling off two or three wickets quickly.''