This passage, appearing in Mekhilta Tractate Nezikin 5:18, restates the teaching of Rebbi (Rabbi Yehudah HaNasi) that appears earlier in the same tractate: "There is 'death' at the hands of Heaven and 'death' at the hands of man. Just as the first leaves no outward sign, so the second." The repetition is deliberate—the Mekhilta applies the same legal principle to a different case within the Torah's civil and criminal code.
In the earlier context (Nezikin 5:7), the teaching addresses the general principle that unspecified capital punishment in the Torah means strangulation, because strangulation leaves no outward mark on the body—mirroring death at the hands of God, which also leaves no visible sign. Here in Nezikin 5:18, the Mekhilta applies the same reasoning to a parallel passage where the Torah again prescribes death without specifying the method.
The fact that Rebbi's teaching appears twice underscores how central it was to rabbinic jurisprudence. This was not an incidental opinion but a foundational legal axiom. Every time the Torah says "he shall be put to death" without further specification, the courts must ask: what does death look like when God administers it? The answer—invisible, leaving the body whole—becomes the template for human justice.
The rabbis' insistence on this parallel reveals their deepest conviction about law. Human justice is not an independent invention. It is a reflection of divine justice. When an earthly court carries out a sentence, it must do so with the same restraint and dignity that characterizes God's own administration of death. The principle applies in every case, which is exactly why the Mekhilta states it twice—once is a teaching, twice is a rule.