In Christianity, the guilt of sin is more than the psychological feeling of guilt that many today have made it. Guilt is a legal concept in Biblical language. It comes before God the judge and it is an objective position not a subjective feeling. That is not to deny the weight of sin emotionally and physically upon a person. Consider:
Psalm 31:9 Be gracious to me, O Lord, for I am in distress; My eye is wasted away from grief, my soul and my body also. 10 For my life is spent with sorrow And my years with sighing; My strength has failed because of my iniquity, And my body has wasted away.
Psalm 32:3 When I kept silent about my sin, my body wasted away Through my groaning all day long. 4 For day and night Your hand was heavy upon me; My vitality was drained away as with the fever heat of summer.
The last line of Psalm 32:4 is a good reminder to us as we go through the heat of the summer right now. the heat can feel oppressive. It drains us. It weighs heavily on us. We can easily identify the heat as the cause. Unfortunately, people often go through life with unconfessed sin or unrepentant of sin as a whole. This can weigh on a person and even, according to the Psalmist, bring physically consequences. (Obvious as a caveat, not all physical issues are the result of sin [direct or indirect] on our part).
Even the person who suppresses the truth of God in unrighteousness may still feel the weight of sin either as a psychological burden or a physical burden. Whoa to the counselor who convinces the sinner they shouldn't feel guilty when they are in fact feeling the effects of the guilt they secretly know they have. You can suppress the truth of God in unrighteousness, but how much more painful to attempt suppressing the effects of suppressing the truth of God in unrighteous.
The way to beat the summer heat is to find the love and foregivness of God through repenting and trusting in the Lord Jesus Christ. And the Christian caught in sin, should appeal to their Advocate in heaven who stands ready to aid and comfort them.