Which ways did Hashem see?
Rashi: When he is humbled in front of Him - affliction came upon him.
Radak: He does not stand for a long time on a good path without sinning and returning to sin.
Radak citing Targum Yonasan: The path of their Teshuvah.
Malbim: The path on which he goes now.
How will Hashem heal him and relieve him?
Rashi: He will lead him in the path of cure, or Anchehu. This is an expression of Hanachah (relief) and rest.
Radak: He will heal his Nefesh via pardoning his sin - this is like "Refa'ah Nafshi" (Tehilim 41:5). Anchehu is to lead him in the good path, i.e. straightening his heart so he will not sin again.
Malbim: Healing applies to what I struck him with afflictions. Relieving him applies to when I hid My face amidst anger. I will cease to hide My face.
Why will Hashem pay consolations?
Radak: It is for the afflictions and evil that he suffered in Galus. I will give to him good to console him.
Who are "Avelav"?
Rashi, Targum Yonasan: Those who are pained over him.
Radak: They are those who mourned in Galus over the Churban of Yerushalayim - "Sisu Itah Masos Kol ha'Mis'abelim Aleha" (66:10).