Rashi on Exodus 5:20/רש"י על שמות ה׳:כ׳

1ויפגעו AND THEY MET — men of Israel met — את משה ואהרן וגו׳ MOSES AND AARON etc.; Our Rabbis explained that wherever it speaks of people “quarelling” (2:13; cf. Rashi on that verse) or “standing” these were Dathan and Abiram about whom it is stated (Numbers 16:27) “[And Dathan and Abiram] came out standing” (Nedarim 64b).