In fact, it's usually the first thing to go. When the attacks get strong, our faith can become weak. We can lose our faith. Our shield will not be lost when we rest, with absolute dependence, in God and God's unconditional and undying love for us. The helmet of salvation is next in our wardrobe.
Salvation is sometimes a misunderstood concept.
This is not what salvation means. The Hebrew word connotes victory over evil or rescue from danger. And in the gospels it is often physical healing that people seek from Jesus, relief from blindness, paralysis, leprosy. Thus, our helmet of salvation is there to keep our minds well, and focused on God. Again, many modern interpreters use this passage to justify a militaristic view of Christianity.