In the Genesis Flood story, what is Noah’s first act after leaving the Ark?

In the Genesis Flood story, Noah’s first recorded act after leaving the Ark is building an altar.

Genesis 8:20 says that Noah builds an altar to the Lord after coming out with his family and the animals. He then takes some clean animals and clean birds and offers burnt offerings on it. The narrative says that God responds to the pleasing aroma and promises not to curse the ground or destroy every living thing in the same way again.

This event comes before the rainbow covenant described in the next chapter. It also explains why Genesis had earlier distinguished clean from unclean animals: the text identifies clean animals and birds as suitable for sacrifice.

The first post-Ark act is sometimes confused with Noah planting a vineyard. The vineyard appears later, in Genesis 9:20. The order is altar first, covenant afterward, and vineyard later.