A good while ago, I was asked about spiritual depression by Theresa, the author of the fantastic blog, My Desert Heart. I haven't stopped thinking about the concept ever since.
I think spiritual depression, a kind of despair of the soul, is a far different thing than what we moderns think of as simply "depression" as such. Depression is often due to a multiplicity of factors, be they environmental, chemical, or whatever else. But spiritual depression is something quite different I think.
My view is this - spiritual depression is a kind of distrust in the Divine Mercy of God, when we boil it all down that is. It is feeling as though one can never be perfect as God is perfect (and as we are all called to be!), a focus on one's own unworthiness without also considering the love and mercy of God that overrides that unworthiness. This is understandable, I think: just as God is unfathomable, so sometimes is His Mercy. And for those of us who are often acutely aware of our own sinful nature, our failings, our pasts, and all the rest, it can be very hard to understand that God's Mercy overrides all of this.
For myself, I often have trouble going up to receive Holy Communion - all I can think of is how I have failed during the week, how many sins I have committed during the week, and the like. But this, I think is a healthy thing to do, especially considering Who it is that they are receiving!
Where I think it becomes unhealthy is when one is not even in a state of mortal sin, and still refuses to receive Holy Communion - why refuse the greatest help we are offered, the greatest solace, the greatest food when we need it the most? It is akin to a man dying in the desert and refusing water to drink because he says he is unworthy of it. Maybe so, but the will to live surely must come into play.
Nonetheless, spiritual depression and despair can be crippling. St. Thomas Aquinas actually lists despair as a sin that causes incredible damage to the soul, saying that it "is not only a sin but also the origin of other sins"1. Truer words have never been spoken from my point of view.
This is why spiritual depression needs to be fought as vigorously as any other major sin, or as any sin at all for that matter. St. John of Karpathos says that "Even if you fall a thousand times because of the withdrawal of God's grace, rise up again each time, and keep on doing so until the day of your death"2.
The ironic thing is that depression of any kind is wallowed in because I believe there is always a benefit to be being depressed, whether we wish to see it or not. I am speaking from experience on this - being depressed meant for me, at least, that I did not have to deal with life, be responsible, nothing. It felt like time had stopped, just for me. But time never stops, and eventually we are called to rise up or continue sitting in our own Slough of Despond.
The best way, I have found, to rise again is to frequent the Sacraments as much as possible. Confession is there for when you fall, to clean you up, patch up your spiritual armor, and get you back into the war. Holy Communion is where we receive the actual Body and Blood of Christ Jesus - never forget that, and how much that fact matters.
And never forget too, if you suffer from spiritual depression, that you are surrounded by a cloud of witnesses - all the angels and saints and the Blessed Virgin herself are all cheering for you. Ask them for help - how often, I think to myself, our Guardian Angels are ignored, when it is they who are assigned to protect us every step of the way from such things.
If you are looking for helpful reading, the diary of St. Faustina was a massive help for me in darker times - every page is chock full of consolation derived from the Divine Mercy of Jesus. St. Therese of Lisieux also writes often about spiritual despair and like subjects. And if you're looking for a work that is a little less "heavy" and more accessible, I find that Henri Nouwen's The Inner Voice of Love to be an enormously helpful book. St. Augustine's Confessions is also an extremely helpful work, one that I think many can relate to.
Just remember: Above all, keep your head up, and don't forget to nourish to your soul as much as you can with the Eucharist and all the other sacraments.
1 - Summa Theologica, II-II, 20, 1
2 - Texts for the Monks in India, 84