1)
How will he be "Meshiv Nefesh"?
1.
Malbim: He returned the Nefesh of Machlon to this world a second time.
2)
Why does it say "Ki Chalasech Asher Ahavasech Yeladato"?
1.
Malbim: He will also support your old age, for he was born to your daughter-in-law who loves you. They will strive to finance your old age.
