I was around 24 years old when I started my career as an Executive Assistant in a PR-Advertising firm. One day, one of my clients told me, "You seem to be so happy with your job". I surely was. I loved my job and people saw it. I believe I even rubbed it on others.
Even way back then, I understood the concept of loving your job. The only way I could get motivated was for me to enjoy what I was doing. Nobody could force me to stay motivated just because I had to. This is why the concept of working just for money never worked for me. There was no way I could wake up in the morning and drag myself to work. I had to feel happy to be motivated.
No matter how difficult or tiring your job can be, if you are happy with it and if you love it, then you will be able to smile in the midst of stress. You will be able to dance and sing in the middle of a deadline. You will be able to laugh even when everybody else is serious. This is the essence of enjoying your job or any work you do for that matter.
Work doesn't have to be all serious. Work should be fun. Colossians 3:17 says: Whatever you do, do it as unto the Lord. If what we are doing is offered to God, then we would want this work to be pleasing to Him. James 1:17 says: Every good and perfect gift comes from the Father. If you have a job that doesn't violate the Word of God, then your job is good and it comes from God. Since it comes from Him, then you have to be thankful and remain thankful at all times.
If you are in a job that you are not happy with, then what the heck are you still doing there? I won't accept "but I need to provide for my family" as a reason. If you are stressed out over your job, you may end up dead pretty soon. So how else can you provide for your family if you are dead?
I understand that it is not so easy to find a job these days, but this is where you can put your trust in God and let Him lead you to that job. This is where you can exercise your faith that His favor surrounds you like a shield (Psalm 5:12). This is where you can test His faithfulness if you have truly obeyed Him. This is where you can commit your works to Him so He can cause your thoughts to become agreeable to His will and so shall your plans be established (Proverbs 16:3).
God knows which job is the best for you. He is the One who will lead you, if you seek Him and obey His voice. So if you are not happy with your job, have faith that God will help you.
Now if you used to love your job and you are losing the passion for it, then it is time to pray and seek God. Let Him expose to you why you are feeling this way. Is He bringing you to a better place? Is He revealing to you something that you need to change about yourself? Is He telling you that you've been slacking? He will be the One to tell you.
In my own experience, when I begin to lose that fire or passion over something I used to have so much passion for, I know that it is God preparing me to move to another level. This may or may not be the case for you. There were also certain incidents in my life when after losing the passion over something, God reveals to me that it was not His plan in the first place. There were things that I became so passionate about that were not God's perfect plan for me, and so the "fire" was not sustained. Again, this may or may not be the case for you.
If you love your job and are so passionate about it, then continue praising God for your job and your love for it. Just remember that God and not your job should come first.