Exodus 19:8

19:8 and all the people answered together, “All that the Lord has commanded we will do!” ¹  So Moses brought the words of the people back to the Lord.

Exodus 19:20

19:20 The Lord came down on Mount Sinai, on the top of the mountain, and the Lord summoned Moses to the top of the mountain, and Moses went up.

¹ tn The verb is an imperfect. The people are not being presumptuous in stating their compliance – there are several options open for the interpretation of this tense. It may be classified as having a desiderative nuance: “we are willing to do” or, “we will do.”