I am currently making lentil soup and hoping to slowly eat it until Thursday night. Will it keep in the fridge until Thurs or should I freeze some?
It will keep, although some vegetables get a bit mushy / funky after several days (like broccoli). It helps to quick cool the soup -- put the pot in a sink of ice water to quickly cool down.
Lentil soup does freeze well, put single servings in a 1qt zip-loc and press out air the seal. To eat, run the bag under hot water, then break up and put in a bowl to heat.