17. Promise is sure
Romans 4:16 Therefore it is of faith, that it might by grace; to the end the promise might be sure to all the seed; not to that only which is of the law, but to that also which is of the faith of Abraham; who is the father of us all.
Romans 4:21 And being fully persuaded that, what he had promised, he was able also to perform.
God will do what He promised; the promise is sure. That itself is a promise. The statement that God will do what He says is a promise of sheer grace; for grace simply says that God does it all for us, and it says that God does everything that needs to be done; we cannot add anything to God’s grace. There is nothing left for us to do whatsoever; and this grace is a sure thing.
The completeness of grace is sure: Jesus has earned it all and God gives it all to us for free. Faith receives the promise. The only thing left for us to do is believe it, and the Holy Spirit of God even gives us the faith to receive the promise. Faith agrees with the Word and Promise of God and faith affirms confidently that everything that needs to be done for us and for our salvation has already been accomplished: it is finished; everything is ready. Eat, drink and enjoy!
The certainty of the promise is spoken to us in the Gospel so that we can live at peace, rest in the comfort, bask in the love and revel in the joy. There is no space left for doubt or uncertainty. God keeps His promises and I am fully persuaded. God loves me and He wants me happy and at peace.