Passage
If after thou hast heard these judgments, thou keep and do them, the Lord thy God will also keep his covenant to thee, and the mercy which he swore to thy fathers:
Deuteronomy 7:12 (DRB)
Nearby Context
Deuteronomy 7:10 And repaying forthwith them that hate him, so as to destroy them, without further delay immediately rendering to them what they deserve.
Deuteronomy 7:11 Keep therefore the precepts and ceremonies and judgments, which I command thee this day to do.
Deuteronomy 7:12 If after thou hast heard these judgments, thou keep and do them, the Lord thy God will also keep his covenant to thee, and the mercy which he swore to thy fathers:
Deuteronomy 7:13 And he will love thee and multiply thee, and will bless the fruit of thy womb, and the fruit of thy land, thy corn, and thy vintage, thy oil, and thy herds, and the flocks of thy sheep upon the land, for which he swore to thy fathers that he would give it thee.
Deuteronomy 7:14 Blessed shalt thou be among all people. No one shall be barren among you of either sex, neither of men nor cattle.
Study Lenses
The verse centers on "mercy", "after", "thou", "hast", "heard", "judgments", "keep", and "lord". It is saying that the verse draws attention to "mercy" and "after", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 11's "Keep therefore the precepts and ceremonies and..." into verse 13's "And he will love thee and multiply...", so "mercy" and "after" belong inside that flow. In Deuteronomy context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "mercy" and "after" with trust shaped by these words, not by a vague optimism outside the passage.