Sayyiduna Ibn Abbas (may Allah be pleased with them both) said, concerning the saying of Allah Almighty: "So he was at the distance of two bow-lengths or even nearer" [Al-Najm: 9]: "Qab means a measure (of distance), and qawsayn means the two arms."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12550