I know a lot of people use Barbara in their party to heal the other characters but there are a lot of people who haven't gotten her yet nor do they have enough food to heal after fights so I have another method.
It's likely that a lot of people know about this but I only found out after reaching level 23 and struggled a lot with healing before level 20 so I think this can be really helpful to a lot of people. If you go to the Statues of the Seven and talk to them, you will get an option called Statue's Blessing.

Statue's Blessing heals you when you stand on the platform in front of the statue but only up to 50% of your health if you havent changed the amount yet.
Once you select the Statue's Blessing option, it will bring up this screen(displaying your characters):

Simply increase the percentage on the left to 100% and it will heal all party members when you step on the platform(and maybe unselected characters but I'm not entirely sure). The restorative power depletes every time the character heals but will recharge over a couple of minutes to hours(depending on how much is used).
I mainly use this after fighting Hypostatis' or when I don't have Barbara in my party and want to save up food for other battles where it may be neccesary.

