"The very conflicts and rebuffs we meet are to make us stronger and give stability to our faith. We are not to be swayed, like a reed in the wind, by every passing influence. Our souls, warmed and invigorated by the truths of the gospel, and refreshed by divine grace, are to open and expand, and shed their fragrance upon others. Clad in the whole armor of righteousness, we can meet any influence and our purity remain untarnished. 4T 556.1"
"Put on the whole armour of God, that ye may be able to stand against the wiles of the devil."
EGW directly references and expands upon the concept of putting on the armor of God.
"But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed."
Both passages contrast stability in faith with being easily swayed, using the imagery of wind and waves/reeds.