سل عن الرفيق قبل الطريق
Ask about the companion before you travel
It is essential before you travel to know who will travel with you. If your travel companion is experienced and well-mannered you will enjoy his company and reach your destination safely. If he was the opposite of that, your trip will be hard and dangerous.
Likewise, your spiritual journey to Allah which takes a lifetime and is more important, requires careful choosing of your travel guide. In this case he is called master, teacher, guru, or shaikh. If he was an experienced and compassionate spiritual guide, you’ll safely reach spiritual perfection. Otherwise, you are in danger of losing the way and might end up in hell.
لو كان لربك شريك لأتتك رسله
If there was another God he would have sent you his prophets.