RobH_en_tn/deu/33/19.md

There will they offer

"It is there that they will offer"

sacrifices of righteousness

"acceptable sacrifices" or "proper sacrifices"

For they will suck the abundance of the seas, and from the sand on the seashore

Possible meanings are 1) they will trade with people across the sea or 2) they were beginning to use sand in making pottery.

For they will suck the abundance of the seas

The Hebrew word translated "suck" here refers to how a baby nurses at its mother's breast. It means the people will gain wealth from the sea like a baby gets milk from its mother. (See: rc://en/ta/man/translate/figs-metaphor)