And that thou mayst love the Lord thy God, and obey his voice, and adhere to him (for he is thy life, and the length of thy days,) that thou mayst dwell in the land, for which the Lord swore to thy fathers Abraham, Isaac, and Jacob that he would give it them.
Deuteronomy 30:18 I foretell thee this day that thou shalt perish, and shalt remain but a short time in the land, to which thou shalt pass over the Jordan, and shalt go in to possess it.
Deuteronomy 30:19 I call heaven and earth to witness this day, that I have set before you life and death, blessing and cursing. Choose therefore life, that both thou and thy seed may live:
Deuteronomy 30:20 And that thou mayst love the Lord thy God, and obey his voice, and adhere to him (for he is thy life, and the length of thy days,) that thou mayst dwell in the land, for which the Lord swore to thy fathers Abraham, Isaac, and Jacob that he would give it them.
The verse centers on "thou", "mayst", "love", "lord", "obey", "voice", "adhere", and "life". It is saying that the verse draws attention to "thou" and "mayst", so its meaning should be read from those terms before moving to application.
The prior verse says "I call heaven and earth to witness...", giving immediate footing for "thou" and "mayst". In Deuteronomy context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "thou" and "mayst" with trust shaped by these words, not by a vague optimism outside the passage.