The word “behold” here adds emphasis to what follows. AT: “Indeed”
## I am for you ##
"I want to do good things to you." The word "you" refers to the mountains of Israel.
## and I treat you with favor ##
"I will be kind to you" (UDB)
## you will be plowed and sown with seed ##
AT: "My people, Israel, will plow your ground and sow it with seed." To plow means to cut rows in the ground in order to plant seeds in them. (See: [[rc://en/ta/man/translate/figs-activepassive]])