Sure Guide to Heaven - Obedience and Inability

Your law will I lay before me; this shall be the copy which I will keep in my eye, and study to write after. According to this rule do I resolve by Your grace to walk: after this law shall my whole man be governed. And though I cannot perfectly keep one of Your commandments—yet I will allow myself in the breach of none. I know my flesh will hang back: but I resolve, in the power of Your grace, to cleave to You and Your holy ways, whatever it cost me. (Joseph Alleine, A Sure Guide to Heaven, pg. 129)

Our inability to perform the Law in no way removes the requirement to obey.

The times of ignorance God overlooked, but now he commands all people everywhere to repent - Acts 17:30, ESV

...but God shows his love for us in that while we were still sinners, Christ died for us. Since, therefore, we have now been justified by his blood, much more shall we be saved by him from the wrath of God. For if while we were enemies we were reconciled to God by the death of his Son, much more, now that we are reconciled, shall we be saved by his life. More than that, we also rejoice in God through our Lord Jesus Christ, through whom we have now received reconciliation. - Romans 5:8-11, ESV

When I Survey the Wondrous Cross
(Isaac Watts)

When I survey the wondrous cross
on which the Prince of Glory died;
my richest gain I count but loss,
and pour contempt on all my pride.

Forbid it, Lord, that I should boast,
save in the death of Christ, my God;
all the vain things that charm me most,
I sacrifice them to his blood.

See, from his head, his hands, his feet,
sorrow and love flow mingled down.
Did e'er such love and sorrow meet,
or thorns compose so rich a crown.

Were the whole realm of nature mine,
that were an offering far too small;
love so amazing, so divine,
demands my soul, my life, my all.

Even in my inability, His great love "demands my soul, my life, my all.