1)
Why does he have Bushah and Kelimah?
1.
Mesilas Yesharim (Perek 10): Only one who totally cleansed himself from any trace of sin is proper to see His countenance. If not, he should feel Bushah and Kelimah in front of Him. Malbim - Bushah is shame that he himself feels. Kelimah is shame from others.
2)
Why does it say "Avonoseinu Rabu l'Ma'alah Rosh"?
1.
Malbim: Avon is crooked Sechel, which is in the head. It went above the head and spread outside. This caused Bushah that he himself feels.
3)
Why does it say "v'Ashmasenu Gadlah Ad la'Shamayim"?
1.
Malbim: Ashmah is liability for punishment. This caused Kelimah - shame from others.
