Q 33. Was the covenant of grace always administered after one and the same manner?
A. The covenant of grace was not always administered after the same manner, but the administrations of it under the old testament were different from those under the new.1
2 Corinthians 3:6-9
who has made us competent to be ministers of a new covenant, not of the letter but of the Spirit. For the letter kills, but the Spirit gives life.
Now if the ministry of death, carved in letters on stone, came with such glory that the Israelites could not gaze at Moses’ face because of its glory, which was being brought to an end, will not the ministry of the Spirit have even more glory? For if there was glory in the ministry of condemnation, the ministry of righteousness must far exceed it in glory.
For if that first covenant had been faultless, there would have been no occasion to look for a second.
For he finds fault with them when he says:
“Behold, the days are coming, declares the Lord,
when I will establish a new covenant with the house of Israel
and with the house of Judah,
not like the covenant that I made with their fathers
on the day when I took them by the hand to bring them out of the land of Egypt.
For they did not continue in my covenant,
and so I showed no concern for them, declares the Lord.
For this is the covenant that I will make with the house of Israel
after those days, declares the Lord:
I will put my laws into their minds,
and write them on their hearts,
and I will be their God,
and they shall be my people.
And they shall not teach, each one his neighbor
and each one his brother, saying, ‘Know the Lord,’
for they shall all know me,
from the least of them to the greatest.
For I will be merciful toward their iniquities,
and I will remember their sins no more.”
In speaking of a new covenant, he makes the first one obsolete. And what is becoming obsolete and growing old is ready to vanish away. (ESV)