Who knows what it means

Could mean that Spinelli knows the "truth" and that is Jason has always wanted to be with Liz.
Spinelli also knows what Sam did.
Could be Spinelli was trying imo to protect Jason cause he thinks Jason is happy
He didn't want Liz to dig up the past and hurt anyone ...

Face it Spinell is the biggest Ho pimp on the show.
So he was just looking out for Ja1.5

Could be he didn't want Liz bringing up the past imo

He maybe it is a sign that the past is going to be brought up regardless ...

that is my wishful thought anyway
that the "dark" scenes are going to be all about what and who Sam is and what she has done