So I was reading through a bit of Isaiah the other day, and while looking through chapter 54, I began sense something familiar about the words. As I continued reading, I realized with great excitement that one of my favorite songs was based on this scripture! The song "Pensive, doubting, fearful heart" had always been a great encourage to me (I got to know it through Red Mountain Music)....especially the very last verse....but never did I realize it was based almost directly from Isaiah. Reading through this Isaiah 54 makes the song even more powerful, as I remember the context and earth-shaking truth of the words.
Here are some of the verses from Isaiah, each followed by the the verse of the song that evidently corresponds. The author, John Newton, was cleary inspired by these beautiful words!

Isaiah 54:1 "Sing, O barren woman,
you who never bore a child;
burst into song, shout for joy,
you who were never in labor;
because more are the children of the desolate woman
than of her who has a husband,"
says the LORD.

Pensive, doubting, fearful heart,
Hear what Christ the Savior says;
Every word should joy impart,
Change thy mourning into praise.

Yes, He speaks and speaks to thee,
May He help thee to believe;
Then thou presently will see
Thou has little cause to grieve.
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Isaiah 54:4 "Do not be afraid; you will not suffer shame.
Do not fear disgrace; you will not be humiliated.
You will forget the shame of your youth
and remember no more the reproach of your widowhood.

5 For your Maker is your husband—
the LORD Almighty is his name—
the Holy One of Israel is your Redeemer;
he is called the God of all the earth.

Fear thou not, nor be ashamed;
All thy sorrows soon shall end,
I, who heaven and earth have framed,
Am thy Husband and thy Friend;

I the High and Holy One,
Israel's God, by all adored,
As thy Savior will be known,
Thy Redeemer and thy Lord.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Isaiah 54:7 "For a brief moment I abandoned you,
but with deep compassion I will bring you back.

8 In a surge of anger
I hid my face from you for a moment,
but with everlasting kindness
I will have compassion on you,"
says the LORD your Redeemer.

10 Though the mountains be shaken
and the hills be removed,
yet my unfailing love for you will not be shaken
nor my covenant of peace be removed,"
says the LORD, who has compassion on you.

For a moment I withdrew,
And thy heart was filled with pain;
But my mercies I'll renew;
Thou shall soon rejoice again;

Though I seem to hide my face,
Very soon my wrath shall cease;
'Tis but for a moment's space,
Ending in eternal peace.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Isaiah 54:11 "O afflicted city, lashed by storms and not comforted,
I will build you with stones of turquoise, [a]
your foundations with sapphires. [b]

12 I will make your battlements of rubies,
your gates of sparkling jewels,
and all your walls of precious stones.

13 All your sons will be taught by the LORD,
and great will be your children's peace.

14 In righteousness you will be established:
Tyranny will be far from you;
you will have nothing to fear.
Terror will be far removed;
it will not come near you.

15 If anyone does attack you, it will not be my doing;
whoever attacks you will surrender to you.

16 "See, it is I who created the blacksmith
who fans the coals into flame
and forges a weapon fit for its work.
And it is I who have created the destroyer to work havoc;

17 no weapon forged against you will prevail,
and you will refute every tongue that accuses you.
This is the heritage of the servants of the LORD,
and this is their vindication from me,"
declares the LORD.

Though afflicted, tempest tossed,
Comfortless awhile thou art,
Do not think thou can be lost,
Thou art graven on my heart;

All thy wastes I will repair;
Thou shalt be rebuilt anew;
And in thee it shall appear
What the God of love can do.