Psalms 25:18

Look upon mine affliction and my pain; and forgive all my sins.

Psalm 25 belongs to a group of psalms linked to the sorrows and afflictions of the Hebrew captives in the Babylonian captivity, probably in its latter part under Belshazzar when Jewish persecution and distress were greatest. That group carries encouragement and assurance of divine help unto final deliverance.
As one of the seven Penitential Psalms, it expresses human need and shows how God helps the soul through discouragement, trial, and grief. It points to God as willing and able to save.
The verse asks God to look upon affliction and pain and to forgive all sins, joining a plea for relief from suffering with a plea for pardon. It is a prayer any burdened person may pray when weighed down by affliction and pain.
The affliction and pain stand alongside the enlarged troubles of the heart, showing the distress is not merely outward but physical and inward. That distress is bound up with the speaker's own disobedience, sin, and need for mercy.
Deliverance from misery is expected through God's forgiveness. God first forgives all iniquities and then heals all diseases, so that a forgiven soul is a healed soul.
Prayer for relief from affliction must include humble confession of the particular sins that concern the work in hand, because particular sins are often joined to afflictions. Filthy garments must be put away by asking first to be delivered from transgression and then to be heard. While the heart is sick with unpardoned sin it stays in dismay and cannot cry strongly to God but must discharge itself in holy groans, since sin like a thick cloud hides God's face so prayers cannot enter. Confession must therefore be shamefaced and crimson with sin and sprinkled with sacrificial blood on the horns of the golden altar before an answer of peace comes from the mercy-seat, and when the person is pardoned the suit is accepted and the petition is crowned with peace.