Fear Not I am With Thee

There are some scriptures that I have memorized just due to having sung songs based on those verses. "For unto us a child is born" or "All we like sheep"

One of my favorite hymns is "How Firm a Foundation"

I particularly like (and have memorized) verses 3, 4, and 5. But somehow I missed that they were based on verses from Isaiah.

3-"Fear not, I am with thee; O be not dismayed!
For I am thy God, and will still give thee aid;
I'll strengthen thee, help thee, and cause thee to stand,
upheld by my righteous, omnipotent hand."

Isaiah 41:10
Fear thou not; for I am with thee: be not dismayed; for I am thy God: I will strengthen thee; yea, I will help thee; yea, I will uphold thee with the right hand of my righteousness.

4-"When through the deep waters I call thee to go,
the rivers of sorrow shall not thee overflow;
for I will be with thee, thy troubles to bless,
and sanctify to thee thy deepest distress.

5-"When through fiery trials thy pathway shall lie,
my grace, all sufficient, shall be thy supply;
the flame shall not hurt thee; I only design
thy dross to consume, and thy gold to refine"

Isaiah 43:2 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.