Lawes was given a week off after playing a huge part in England's run to the Rugby World Cup semi-finals.
He returned to the six shirt for the home clash with Exeter Chiefs, and it was a happy homecoming for the Saints legend as his side secured a bonus-point 34-19 Gallagher Premiership success.
"It's good to be home and be back with the family," Lawes said.
"It's just so different when you've got a family and you're away so it's good to come home and be back out there at the Gardens.
"It's great to start with a W.
"We work really hard as an England team and you're just seeing that because you go away and you're playing against the best players in the world so everything's a bit harder.
"You come back to the Prem and you just try to maintain that same consistency. You're seeing that this week with the boys playing."
Alex Mitchell was also back in action for Saints, starting at scrum-half and scoring during the second half.
Saints turned in a superb overall performance as they saw off the side who had started the weekend top of the Premiership table.
And Lawes said: "We can be very happy with that. We played a really good tactical game and scored some great tries.
"It's good to be playing that kind of rugby in this kind of weather, and we'll take the five points.
"We've got Lee (Radford) in now and he's done a great job. You can't win Premierships without a great defence so it's something we'll keep working on and look to get better at as we build into the season.
"Bath were top last week, Exeter were top coming into this weekend so we're showing we can mix it with the big boys and we'll just try to keep building."
Lawes believes Saints have improved this season, having finished fourth in the previous campaign.
And he added: "Training wise we're just a lot clearer.
"We're pretty physical with each other on a week to week basis from what I saw during the week and it all goes into building a strong defence.
"You've obviously got to be careful you don't overdo that, the physical side, and you've got to make sure you're mentally ready for the game."
Saints have made it clear that they are desperate to achieve a top-two finish and a home semi-final in the Premiership this season.
"Anyone is in with a shout of top four and then into the semi and final, anyone can win these games," said Lawes, who announced his England retirement at the end of the World Cup.
"We have to take each game as it comes, pick up as many points as possible and try to get a home semi-final because that's what we're striving for.
"You really can't look ahead but as long as we keep building on this performance, we'll have a great season."