7:12 Wherefore it shall come to pass, if ye hearken to these judgments, and keep, and do them, that the LORD thy God shall keep unto thee the covenant and the mercy which he sware unto thy fathers:
Comment: This verse starts a new portion named “eiqev”. This word “eiqev” is translated to be “if” in the above kJV Bible translation. However, according to Rashi’ commentary, the word “eiqev” originally means “heel”, which I interpret it to mean “following” (as the heel follows a man’s walking), or “as a consequence of”. This Hebrew word “eiqev”עקב seems to be very similar to a Chinese word “gen跟”, which has both the meaning of “heel” and “following”. Following your deeds, will come consequences. As a consequence of your obeying Gd’s instructions, Gd’s blessings will follow.
7:13 And he will love thee, and bless thee, and multiply thee: he will also bless the fruit of thy womb, and the fruit of thy land, thy corn, and thy wine, and thine oil, the increase of thy kine, and the flocks of thy sheep, in the land which he sware unto thy fathers to give thee.
Comment: You will be blessed with material goods, but many of these blessings will only be realized in your promised land, which will be very different from the wilderness that you are now familiar with. There, in the new living environment, you will be able to plant corn or grow grape vines and olive trees, and be blessed with their fruits, following your obedience to Gd.
What is “the land which he sware unto thy fathers to give thee”? For Jews, this is their promised land in the Middle East. For the whole mankind, Gd has promised the whole earth unto “thy fathers” Adam (Genesis 1) and Noah (Genesis 9).
I think Christians who obey Gd will also be blessed with material goods on the earth, but their blessings will only be realized partially in this world. The rest of their blessings will be realized in a new “world to come” (ha olam haba) in the millennium kingdom, and also in the eternal new Jerusalem between the new heaven and the new earth (Isaiah 11, 65, Revelation 20,21,22).
8:10 When thou hast eaten and art full, then thou shalt bless the LORD thy God for the good land which he hath given thee.
Comment: That is why Jews thank Gd after the meals https://en.wikipedia.org/wiki/Birkat_Hamazon. However, I think it is logical to apply this obligation to any human being who “hast eaten and art full”, that he should thank Gd for the “good land” which he hath given, because the entire earth is given to the mankind (Genesis 1,9), and Gd brings out food from the earth.
This contrasts manna from heaven in that we have a bigger share to work together with Gd to bring out food from the earth. This may lead to someone forgetting Gd and attributing his success to his own abilities…
8:17 And thou say in thine heart, My power and the might of mine hand hath gotten me this wealth.
Comment: Many atheists think this way. They rely on their own abilities.
8:18 But thou shalt remember the LORD thy God: for it is he that giveth thee power to get wealth, that he may establish his covenant which he sware unto thy fathers, as it is this day.
Comment: But who gives people talents and abilities? The top scientists should even be more thankful to Gd for their unusual talents, since they could have been born into the half of the population with below-average IQs. We as believers should thank Gd for giving us abilities to succeed. Even keeping one’s abilities is not to be taken for granted. Even though I was a very productive researcher, when I had health problems in 2002, I found it difficult even to edit a paper for a very minor invited revision. So later when I recovered and became productive again and got promoted in work, I know that ultimately it is Gd’s grace, not my ability, that gives me success.
9:9 When I was gone up into the mount to receive the tables of stone, even the tables of the covenant which the LORD made with you, then I abode in the mount forty days and forty nights, I neither did eat bread nor drink water:
Comments: Moses went up to Mount Sinai (or Horeb) to receive the first set of stone tablets, after Gd announced the 10 commandments (Exodus 20) and established His covenant with His people (Exodus 19, 24). The purpose of these two stone tablets may be likened as two witnesses of the covenant between Gd and His people. (See John 8:17 “It is also written in your law, that the testimony of two men is true”. )
Regarding the material used for these two stone tablets: I noticed that “stones” in Hebrew is “avanm”אבנים, which is a concatenation of “father” (“av”אב ) and “children” (“vanim” בנים). So written in the original holy text, the two words “father” and “children” combine into one word “stones”, which can signify the unification between Gd /Father and his people / children, who are bound together by this covenant between them. 
(: This connection between 2 tablets and 2 witnesses is based on a Jewish Midrash, and it’s mentioned together with several other connections related to “2”, in this linked article: https://www.notredamedesion.org/archived/www.notredamedesion.org/en/dialogue_docsd47e.html?a=3b&id=604.)
(: This idea is transformed from Rashi’s comment on Genesis 48:24, regarding the composition of the singular word “stone”אבן=אב+בן.)
10:12 And now, Israel, what doth the LORD thy God require of thee, but to fear the LORD thy God, to walk in all his ways, and to love him, and to serve the LORD thy God with all thy heart and with all thy soul,
Comment: Is everything pre-determined by Gd, such as one’s IQ, race, sex, year of birth, family, marriage, biological features, children, even the personal characters such as timidity or bravery, laziness or diligence? According to Rashi’s interpretation of the current Bible verse, the answers “yes”: everything is predetermined, except things related to obedience to Gd [which include fearing Him, walking in His ways, loving Him, serving Him, and (v13) keeping His commandments]. These are the only things Gd “require of thee”. The choice is on you and the consequences are also on you. Whatever you are born with, there is no excuse, you still are fully capable and responsible to choose to obey Gd to earn His blessings and to avoid punishments. Gd could have also predetermined our obedience to Him, but that way He would then be like a workman operating a machine, instead of like a Father involving His children to work together with Him.
11:13 And it shall come to pass, if ye shall hearken diligently unto my commandments which I command you this day, to love the LORD your God, and to serve him with all your heart and with all your soul,
Comment: The “ye”, “your” here are plural in Hebrew.
11:15 And I will send grass in thy fields for thy cattle, that thou mayest eat and be full.
Comment: The “thy”, “thou” here are singular in Hebrew. If the whole nation obeys Gd, then each individual will be blessed. Therefore it’s not enough to“mind your own business”, even for the sake of your own wellbeing.
11:21 That your days may be multiplied, and the days of your children, in the land which the LORD sware unto your fathers to give them, as the days of heaven upon the earth.
Comment: The “your”, “them” here are plural in Hebrew. The purposes of Gd’s commandments are good for Gd’s people, both collectively and also in the long run.
It is wrong for some Christians to think about the laws negatively. It is true that salvation is not earned by obeying laws but due to Gd’s grace. Even the Israelites were saved from the Egyptian slavery before they observed the laws. However, Gd can use His laws to direct His peoples’s efforts and to bestow blessings on them, after saving them from slavery (or from sin for Christians). Even human laws such as the traffic rules are beneficial (e.g. for safety), let alone Gd’s laws. Gd is good so His laws must be good. They may be good even for an individual, even for nowadays. I had firsthand experience that by not working on the seventh day each week, my health improved. (Previous to that, I had health problems which made me call 911 twice in 2002. )