1)
When will he praise with song?
1.
Radak: When Hashem will take him out of Galus.
2)
What is the difference between praising with song and thanking "b'Sodah"?
1.
Radak: The latter is thanking for His Chesed and offering a Korban Todah.
2.
Malbim: The former is telling His general praises. The latter is bringing a Todah to thank for His benefits special to me.
