1)
Why does it say "Yehi Shem Hashem Mevurach me'Atah v'Ad Olam"?
1.
Radak: The creations will bless Him. All with Da'as are obligated to bless Him. Me'Atah is now; v'Ad Olam is the future.
2.
Malbim (1): Praise is due to His grandeur; also idolaters admit to this. They call him the G-d of gods. We must also bless Him, for His constant influence via Hashgachah Pratis, which idolaters deny. Through telling (His Hashgachah), His name will always be blessed.
