Into the depths of the sea!

(Thomas Boston, "Human Nature in its Fourfold State")

The sinner outside of Christ is bound over to the wrath of God. He is under an obligation in law to go to the prison of Hell, and there to lie until he has paid the utmost farthing.

But "there is now no condemnation for those who are in Christ Jesus." Romans 8:1

The believer's sins are pardoned, and the guilt of them is removed. The bond obliging him to pay his debt is canceled. God the Father . . .
  takes the pen,
  dips it in the blood of His Son,
  crosses off the sinner's accounts,
  and forever blots them out of His debt-book!

Being united to Christ, God says, "Deliver him from going down to the pit-for I have found a ransom!" Job 33:24

The sentence of condemnation is reversed, and the believer is absolved and set beyond the reach of the condemning law. His sins, which previously were set before the Lord, Psalm 90:8, so that they could not be hidden-God now takes and casts them all behind His back, Isaiah 38:17. Yes, God "will tread our sins underfoot, and hurl all our iniquities into the depths of the sea!" Micah 7:19

What falls into a brook may be retrieved-but what is cast into the sea cannot be recovered.

But there are some shallow places in the sea. True, but their sins are not cast there-but into the depths of the sea. The depths of the sea are devouring depths, from whence their sins shall never come forth again.

But what if they do not sink? God will hurl them in with such force that they shall go to the bottom, and sink as lead in the mighty waters of the Redeemer's blood!

Their sins are not only forgiven-but forgotten. Jeremiah 31:34, "I will forgive their iniquity, and I will remember their sin no more." And though their after-sins do in themselves deserve eternal wrath, and do actually make them liable to temporal strokes, and fatherly chastisements, according to the tenor of the covenant of grace, Psalm 89:30-33-yet they can never be actually liable to eternal wrath.