In winning their 22nd straight home game, the Celtics opened an 18-point lead three minutes into the second quarter and withstood a late rally by the Nets.
Bird, who scored 42 points Friday night against Seattle, had 32 by the end of third quarter as the Celtics took a 92-76 advantage into the final 12 minutes.
"I like it when Larry decides to take over," Celtic Coach K.C. Jones said. "It's easier for me to relax."
An 11-2 run by New Jersey cut the Boston lead to 109-101 with 1:42 left, but the Nets got no closer.
Portland 115, Chicago 113--Kiki Vandeweghe scored 28 points and the Trail Blazers overcame a 46-point night by Chicago's Michael Jordan at Portland.
Portland trailed, 86-74, with 1:19 left in the third quarter, but scored 11 straight points to pull to within one on a free throw by Clyde Drexler with 10:34 remaining.
Steve Johnson, who scored 10 of his 24 points in the fourth quarter, kept the Trail Blazers close until Terry Porter stole the ball and fed Jim Paxson for a layup that gave Portland the lead for good at 111-110 with two minutes left.
The Bulls had a chance to tie the game at the end, but Portland's defense kept the ball away from Jordan, forcing Elston Turner to take the final shot, which missed.