I just want my fellow nairalanders to please throw more light on my question, a friend of mine quit his job because he said he wants to spread the gospel; is it a good idea or not? Though i made him to understand that he can still be working and evangelism in order not to be a liability on anybody, is it a good idea or bad one?

God will provide for him.

Your friend is on the right path, as religion in Nigeria makes more money that the oil industry.

He is good.

Wow...
That's huge. Well, it depends on his conviction.
They say every man must have a personal communication with God. If the connection is there, whatever he says you do. Elijah wasn't rich, but didn't lack. God have a way of taking care of his own. So if he is certain of his conviction, let him be, he will do just fine, might not be great, but will survive.

Let's read other opinions

Let your friend be. You are not the one who placed in him the desire to reach the lost with the gospel of Jesus Christ. He is only putting into action his divine mandate to preach the gospel.

God can take care of his needs so don't worry about his quiting his job. Only, I would that he seeks God to know Him personally then he would receive direction from God on how to go about spreading the gospel.

Don't judge others! Ministry is a call. I think he should have his church as a support base let him discuss it with his pastor except God instructed otherwise.