New Revised Standard Version
If you heed these ordinances, by diligently observing them, the LORD your God will maintain with you the covenant loyalty that he swore to your ancestors;

Contemporary English Version
If you completely obey these laws, the LORD your God will be loyal and keep the agreement he made with you, just as he promised our ancestors.

New American Bible
As your reward for heeding these ordinances and keeping them carefully, the LORD, your God, will keep with you the covenant mercy he promised on oath to your ancestors.

Douay-Rheims Bible
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:

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:

if [heb] because

Deuteronomy 28:1 Now if thou wilt hear the voice of all his commandments, which I command thee this day, the Lord thy God will make thee higher than all the nations that are on the earth.

Leviticus 26:3 If you walk in my precepts, and keep my commandments, and do them, I will give you rain in due seasons.

Lord

Deuteronomy 7:9 And thou shalt know that the Lord thy God, he is a strong and faithful God, keeping his covenant and mercy to them that love him, and to them that keep his commandments, unto a thousand generations:

Psalm 105:8-10 He hath remembered his covenant for ever: the word which he commanded to a thousand generations. . . .

Micah 7:20 Thou wilt perform the truth to Jacob, the mercy to Abraham: which thou hast sworn to our fathers from the days of old.

Luke 1:55,72,73 As he spoke to our fathers: to Abraham and to his seed for ever. . . .