Bale dispatched a clinical header from Tom Huddlestone's cross in the 15th minute as we dominated the first half only for the home side to push us back for long periods after the break.
Clint Dempsey finished from close range to double the lead before the interval but Southampton were a different team in the second half, got a goal back through Jay Rodriguez and pushed us all the way.
Andre Villas-Boas made four changes to the team that started against NK Maribor in the Europa League on Thursday night.
Brad Friedel was back in goal for Hugo Lloris, William Gallas came in for Kyle Naughton, Bale for Andros Townsend and Dempsey for Gylfi Sigurdsson.
We completely controlled the first half.
Aaron Lennon went close inside three minutes and Jermain Defoe was inches wide from Kyle Walker's low cross from the right.
We opened the scoring after 15 minutes. Huddlestone floated the ball up invitingly for Bale to attack and he powered home his header across Artur Boruc.
Danny Fox did well to turn a dangerous Bale cross away from goal and from the corner, Bale and Huddlestone combined again, this time Bale headed just over.
Defoe had a carbon-copy chance to his first of the game from another Walker cross in the 28th minute, but skied his effort.
The second goal arrived on 39 minutes. Lennon darted forward, cutting in from right to left and fed Defoe, he slid his shot beyond Boruc but Jose Fonte looked set to clear, only to slip and Dempsey was there to smash home from two yards out.
Having looked so comfortable at half-time, the second half was a completely different story as Southampton stepped up a gear.
Defoe fired the first chance of the half high into the stand on 47 minutes but Jason Puncheon's volley just wide seconds later seemed to invigorate the home team.
Fox fizzed a 30-yarder over, Rodriguez flicked wide from Ricky Lambert's cross and then Maya Yoshida was inches away after Fonte intially caused havoc from Lallana'a free-kick.
The Saints didn't have to wait long to reduce the deficit though. Fonte rose well to meet a corner, Brad Friedel did even better to keep it out but Rodriguez was there to bundle home the rebound.
Rodriguez fired just wide three minutes later and Gallas did well to block from Lambert.
Defoe threatened to break clear in the 72nd minute only to be denied by a last-ditch tackle from Yoshida, but it was a rare attack as Southampton piled forward again, Lallana played a one-two with Lambert and squared from the byline but Gallas was there to make a key clearance. Rodriguez then fired wide again from 20 yards.
We dealt well with the ball coming into the box for the next 10 minutes and Southampton's final chance was denied by defending that typified the final quarter - Gallas blocking from Mayuka and then Sandro getting in the way of Schneiderlin's thunderbolt follow up - with his head.
Southampton (4-4-2): Boruc; Clyne, Fonte, Yoshida, Fox (Reeves, 78); Puncheon (Mayuka, 58), S Davis (Do Prado, 78), Schneiderlin, Lallana; Lambert, Rodriguez. Unused subs: K Davis, Hooiveld, Ward-Prowse, Chaplow.
Spurs (4-2-3-1): Friedel; Walker, Caulker, Gallas, Vertonghen; Huddlestone (Livermore, 63), Sandro; Lennon, Dempsey (Dawson, 90+3), Bale; Defoe (Sigurdsson, 78). Unused subs: Lloris, Naughton, Falque, Townsend.
Goals: Spurs - Bale (15), Dempsey (39). Southampton - Rodriguez (66).
Yellow cards: Spurs - Sandro (65), Vertonghen (75), Livermore (90+3).
Referee: Mr L Mason.