I am an crystal meth survivor. I lived through that nightmare for two years, but I was stronger than the drug. I became addicted when my gilfriend's sister, a devout Christian, got her hooked on the drug by giving her large amounts for free. I tried my best to help my girlfriend, but in the end I only got hooked myself. Her sister began selling to us and all of our friends to support her own addiction, but she made a lot of money and was dealing with extremely dangerous people. I was in a cycle and I couldn't get out. After my girlfriend's sister got arrested and had to give up legal custody of her only son, we both gave up the drugs got clean.
I am sorry to tell you, but God alone will not help your husband and neither will you. In fact, both you and God will push him further toward the drugs. The truth is crystal meth COMPLETELY changes your mental and physiological state of being. The only thing that will save your husband is to check into a rehab facility for an extended duration, coupled with intensive psychotherapy. He will need to drastically change his surroundings to get away from the people selling him the drugs. Moving often is necessary for hardcore addicts. Doing manual labor will help him immensly because both his mind and body are extremely weak. Unfortunately, jail time may also be necessary for longtime users.
My heart truly goes out to everyone that has to go through this, both the user and their friends and family. But personally, at the same time, I have a little less sympathy for the addicts because they have a choice. In the beginning, I remember destinctly making up my mind every time I wanted to use and didn't want to use. I had a choice, and more often than not, my choice was to be selfish, neglect my loved ones, call in sick to work, and use. Even in your husband's case, being a longtime user and all, he still has a choice. Don't forget that.