Church leaders have also taught that when we take the sacrament, we renew not only our baptismal covenants but “all covenants entered into with the Lord.”4
Straight from the church website. Its all over the place, conference talks "By partaking of the sacrament we renew all covenants entered into with the lord L Tom Perry April 2006", church website and even the new edition of the church handbook states in section 28.0 that "while performing proxy ordinances, they are able to reflect on their own covenants and their commitment to keep those covenants" (nothing about renewing). Partaking the sacrament renews ALL of our covenants that we have made the our Heavenly Father (Temple ones too).
MY 2 pennies: Covenant is a 2 way promise, he promises us things if we do our part. We fall short and are imperfect. It is my understanding that we cannot just say "okay I messed up, now I am going recommit myself to that covenant". We need a way to repent and be forgiven and renew those covenants. That is where the repentance process and the sacrament comes into play. When we go to the temple and do proxy work, we are only doing the work for the dead, and not renewing our temple covenants. Although it is good to learn and relearn and understand what those promises and blessing are that we have made. But they are renewed at sacrament.
