New Defender's Study Bible Notes
6:17 a flood. The Flood (Hebrew mabbul) was a unique event. Various other words were used in Scripture for local floods. The mabbul was the Flood.
6:17 every thing that is in the earth. The purpose of the Flood–to destroy all flesh–could only have been accomplished by a worldwide deluge. The idea of a local flood is merely a frivolous conceit of Christians seeking to avoid imagined geological difficulties. Although many marine organisms would perish in the upheavals, everything in the earth (that is, “on the land”) would die.