My husband (age 26) got a severe lower back pain first time ever. No traumas. Is there anything that can help ease it until we get to the doctor?

Refer to answer. Usually ice and stretching helps. Avoid spine loading exercises. Also avoid too much protein especially protein supplements. If within a week pain does not go away, see your doctor and make sure you do not have uti.
Heat too. Ice/heat combo therapy is great for acute back pain that is so frequently caused by muscle tightness or spasm. Ice is good for inflammation, pain and swelling but will leave the muscles tight. Follow the ice (15-20 min) immediately with heat (15-20 min), moise preferably, which will relax the spasm. Gentle massage can't hurt either to help break the tightness. Hold gentle pressure on the spasms.