Albert Barnes Commentary Isaiah 48:17

"Thus saith Jehovah, thy Redeemer, the Holy One of Israel: I am Jehovah thy God, who teacheth thee to profit, who leadeth thee by the way that thou shouldest go." — Isaiah 48:17 (ASV)

Your Redeemer - (see the notes at Isaiah 41:14; Isaiah 43:1).

Which teaches you to profit - Teaching you what things will most contribute to your welfare. The reference here is chiefly to the afflictions which they suffered in Babylon.

Which leads you - I am your conductor and guide. God taught them, as he does his people now, by his Providence, his revealed word, and his Spirit, the way in which they ought to go. It is one of his characteristics that he is the guide and director of his people.