Psalm 91:4b - God's Faithfulness And Truth Will Protect And Defend Us.

Psa 91:4b (KJV) His truth shall be thy shield and buckler.

Psa 91:4b (TEV)  His faithfulness will protect and defend you.

Psa 91:4b (CWB) His truth will defend and protect you.

Psa 91:4b (TLB) His faithful promises are your armor.

God is a shelter, a refuge when we are afraid. The writer's
faith in the Almighty God as Protector would carry him through all the
dangers and fears of life. This should be a picture of our
trust--trading all our fears for faith in him, no matter how intense our fears.
To do this we must "dwell" and "rest" with him (91:1). By
entrusting ourselves to his protection and pledging our daily devotion to
him, we will be kept safe. [Life Application SB]

He that by faith chooses God for his protector, shall find all
in him that he needs or can desire. And those who have found the
comfort of making the Lord their refuge,.... Whatever is done, our
heavenly Father's will is done; and we have no reason to fear. [Matthew
Henry Commentary]

Christ is the example of One who dwells in God's very shadow.
When tempted, Jesus had no need to prove God's loving care by leaping
from the temple's highest point. He knew, without any need to test
God, that the LORD had commanded "His angels concerning you to guard
you in all your ways" (v. 11). [The 365-Day Devotional Commentary]

When thou passest through the waters, I will be with thee; and
through the rivers, they shall not overflow thee: when thou walkest
through the fire, thou shalt not be burned; neither shall the flame
kindle upon thee. Isa 43:2 (KJV)