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Repeating earthquakes, or repeaters, which repeatedly rupture the same location and release the strain energy, are interpreted as repeated ruptures of an isolated asperity patch surrounded by a stable sliding regime. While repeaters are frequently observed along plate‐boundary faults, the occurrence of repeater sequences are reported in various tectonic settings. Here we systematically investigate whether repeaters occur in the continental crust and subducting slabs beneath the Japanese Islands and show a prevalence of repeaters in both locations. The crustal and intraslab repeaters show the power‐law decay of seismicity rates that is identical to that along plate‐boundary faults and occur on well‐defined fault planes coincidentally with non‐repeating earthquakes. These observations suggest that repeaters share a common generation process independent of the tectonics regime and are not distinct from non‐repeaters in their source locations and occurrence times. We thus infer that repeaters and non‐repeaters are both generated by ruptures of locked asperities in response to stress loading by aseismic slip in the surrounding stable regime. Repeater sequences can be observed when aseismic slip is large enough to rupture an isolated asperity more than twice, while no repeaters are generated when the amount of aseismic slip is not sufficient to cause multiple ruptures at an isolated asperity. Since an earthquake cannot be triggered unless the amount of the aseismic stress loading exceeds the strength of asperities at the fault, hidden aseismic slip probably occurs repeatedly and frequently during an interseismic period. Plain Language Summary: The majority of earthquakes occur at three places in the Earth; along plate boundaries where two plates are adjacent, in downgoing plates (slabs), and in continental plates. However, whether the same generation mechanism works for the earthquakes in the different tectonic regimes is still debatable. Earthquakes with very similar waveforms have been recognized since ∼1900, and we recognize at present that many of such similar earthquakes are repeating earthquakes, or repeaters. The repeaters are caused by repeated ruptures of an isolated, frictionally locked asperity patch by stress loading due to aseismic slip in the surrounding stable regime. This study reveals that these repeaters occur prevalently in both the continental crust and slabs beneath the Japanese Islands. We find that there are no substantial differences in the hypocenter locations and occurrence time between repeaters and non‐repeaters. These observations suggest that all earthquakes share a common generation mechanism. We hypothesize that aseismic slip plays an essential role in stress loading to frictionally locked areas and an earthquake occur when the amount of aseismic slip exceeds the strength of faults. Our idea, although it needs further verification, will help better understanding of how frequent aseismic slip occurs and how earthquakes are triggered. Key Points: Repeating earthquakes are more common in the continental crust and subducting slabs than previously consideredRepeaters are not distinct from non‐repeaters in their source locations and occurrence timesRepeaters and non‐repeaters are triggered by ruptures of locked asperities by stress loading of aseismic slip [ABSTRACT FROM AUTHOR]