Notice how Luke blends into his account both law and the Spirit. The family are religiously scrupulous--in ways that may no longer be applicable in their specifics but are admirable in their attentiveness. They come to the temple because their religious practices require it. Simeon comes to the temple because he has been led by the Spirit.
Look around you at church Sunday. The people you will see there have come because they think it is the right thing to do, the expected thing. And you will see people who have been led there by the Spirit. And for some, both apply.