Deuteronomy 6:8 Therefore thou shalt keep the commandments of the Lord thy God, to walk in his ways, and to fear him.
Always ask: What is the therefore there for? It signifies a cause and effect relationship. You will keep the commandments, live accordingly, and fear God, because of what the Lord has done for you for salvation and provision. We do not keep the commandments to attain salvation, but because we have already been granted it by free grace.
Once we have received life by faith we walk in newness of life. In truth, the entire life of a Christian is a response of thanks. It is as Luther says: “And all this purely out of fatherly divine goodness and mercy, for all which it is my duty to thank and praise, to serve and obey Him.” Thankfulness is our response; thankfulness is our life.
We need to get the cause into our life in order to elicit the response of keeping the commandments, walking in His ways, and fearing the Lord. Fearing God is believing God and His Word so strongly that we want live according to His Law. This kind of faith is produced by hearing and reading the gospel as often as possible. After we are reinforced in our faith we have the desire and power to walk in His ways. Thus we remember God’s goodness and mercy, and apply it to life.