Combine the strawberries with the honey and sugar in a large, non-reactive pot and stir in the thyme leaves. Let it sit for 15 minutes (or up to overnight in the fridge) to macerate (a fancy name for “get all nice and juicy”). I usually use the same pot I plan to cook the jam in, but if you plan to refrigerate the mixture overnight I suggest using a glass bowl instead, as you do not want to heat anything directly from the fridge over your stove top.
The mixture should look syrupy and delicious. Add the lemon juice and heat the mixture in your non-reactive pot over medium high heat. Stir regularly for 40-50 minutes until it reduces and reaches its gel point, which should be at around 220°F. A spoon should be able to be dragged across the jam without immediately rushing back to fill the space.
Once the jam has reached your preferred consistency, add the rum and continue to cook for only 2-3 minutes more. Remove from heat.
Using proper canning procedures, pour into prepared jars leaving a ¼ inch headspace, wipe the rims clean, place on the lids, and tighten the rings to finger-tip tightness. Process for 10 minutes in a water bath canner to seal.
Properly sealed jars will keep for up to one year in a cool dark place. Once opened, store in the fridge and eat within 2-3 weeks.