It’s referring to after the captivity when they return to God to obey. And that’s the ‘you’ in this section: you shall again obey.
More than that, verse 11 says it’s “not too difficult for you, nor is it out of reach.”
We have His word right in our hands. And what it asks is not tough. Especially for us as New Testament believers – love God, love your neighbor. Love covers it.
On top of that, we have the Holy Spirit to guide us, indwell us, empower us, etc. We really have no excuse. We’re human – that’s an explanation.
We are fallen and it should all point us back to how great He is, how He deserves glory and our worship and how we don’t know it all and need Him. Always turn back to Him.