Grief is a personal process. Keep in mind that each individual handles it differently and in varying degrees and stages. If your husband loses his dad, it's not unusual to experience some uncertainty as to how you can help. On a practical level, you can ask if he wants you to help make funeral arrangements or help with other family matters such as assisting his mother sort through his father's things. You can also show your support by providing a shoulder when he needs one as he deals with his loss.
Listen
Take your cues from your husband. If he needs some time alone, let him have it; however, let him know that you're there to listen to him if he wants to talk, notes HelpGuide.org. Understand that he might not talk about the death at all, so don't force the issue. Realize that if he does want to talk he might want to talk about the good times he had with his father, or maybe the not so great times. He might feel a sense of guilt, which is also normal. Allow him to express these thoughts, and remind him that no matter what, you're not going anywhere and you will continue to listen to, and support, him. Don't interrupt your husband while he's talking, but do make sure that he knows you're paying attention by nodding or reaffirming that you understand.
Provide Physical Comfort
If your husband is an affectionate person, he may need a sense of physical comfort during this difficult time. Hug him or hold his hand to remind him that you are physically there for him, too. If your husband is not the hugging type, just touching his shoulder lovingly or wiping his tears might be enough to comfort him. If he pulls away, respect his space, but always welcome him with open arms if he expresses the need for physical warmth and affection.
Give Him Time
While some people grieve for a few days or weeks, others grieve for years. Let your husband know that there is no rush to "going back to normal" or ending the grieving process. By giving him permission to take all of the time he needs, you will be assisting him in coping with his loss. However, pay attention to his mood and behavior as time goes on. While it's not unusual to grieve for a long time, if your husband becomes detached, withdrawn, experiences changes in appetite or loses his sex drive, you might want to encourage him to seek professional help, as these behavior can signal depression, which may require medication to treat, notes Dr. Marie Harwell-Walker in a Psych Central article.
Let Him Seek Comfort in Other Loved Ones
Your husband might feel that it's particularly important to have some time with his siblings or other relatives during his grieving process. Allow him the time and space he needs to interact with his family who may be able to help him through this difficult process in their own ways. Remember that while you should be his rock, you may not be able to relate to him in the same sense that his siblings or relatives can in regards to his father.