The word of God is not only inerrant, it is also effective. (Isaiah 55:10-11).
VDMA stands for Verbum Domini Manet in Aeternum and means “The Word of the Lord Endures Forever.” This “is the motto of the Lutheran Reformation, a confident expression of the enduring power and authority of God’s Word. The motto is based on 1 Peter 1:24-25.” (Concordia: The Lutheran Confessions, 2).
The symbol VDMA set around a Greek cross “first appeared in the court of Frederick the Wise in 1522. He had it sewn onto the right sleeve of the court’s official clothing, which was worn by prince and servant alike.” (Ibid):
“Heaven and earth will pass away, but my words will never pass away.”
(Luke 21:33).
Light from Light 
I like your reference:
The word of God is not only inerrant, it is also effective. (Isaiah 55:10-11).
but I think a better word would be “efficacious,” instead of effective.
Something can be efficacious, that is having the power to accomplish an effect, without necessarily being effective (producing that effect). For example, Scripture always has the power to call someone to faith, even though an individual may reject its message.