If ye be willing and obedient. Rosenmüller explains this as equivalent to "if ye be willing to obey" (cf. Ezekiel 3:7); but perhaps it is better to give each verb its separate force: "If you consent in your wills, and are also obedient in your actions" (so Kay).
Ye shall eat the good of the land; i.e. there shall be no invasion; strangers shall not devour your crops (see Isaiah 1:7); you shall consume them yourselves. "The good of the land" is a common expression for its produce (Genesis 45:18, Genesis 45:20; Ezra 9:12; Nehemiah 9:36; Jeremiah 2:7).