Lamp, oil, and heated iron

Meaning

Cold iron warmed through repeated motion and a lamp requiring continued oil illustrate the need to sustain inward spiritual life in Part IV: the spiritual comparison · unit 44. The two examples do different work: motion shows stimulation, while the lamp shows gradual diminution when appropriate support ceases. They support an exhortation to hear, consider and practise God's Word. The English's 'lamp' avoids reading the historical noun through an unrelated modern German sense. These are ordinary-world analogies alongside the philosophical fire, not instructions to combine iron and lamp oil in the material work.