Produce spiritual fruits in any circumstance

Mark 11:12-26
Seeing in the distance a fig tree in leaf, he went to find out if it had any fruit. When he reached it, he found nothing but leaves, because it was not the season for figs. When he reached it, he found nothing but leaves, because it was not the season for figs. Then he said to the tree, “May no one ever eat fruit from you again.” And his disciples heard him say it.
Peter remembered and said to Jesus, “Rabbi, look! The fig tree you cursed has withered!”
 “Have faith in God,” Jesus answered. Therefore I tell you, whatever you ask for in prayer, believe that you have received it, and it will be yours. 
And when you stand praying, if you hold anything against anyone, forgive them, so that your Father in heaven may forgive you your sins.”
And as he taught them, he said, “Is it not written: ‘My house will be called a house of prayer for all nations’? But you have made it ‘a den of robbers.’
Why?
Church is a place of prayer and worship the Lord, it is not for business, even not allow make business of worship.
Q:Why did Jesus curse a fig tree while he was walking with his disciples toward Jerusalem?
The tree in question did have very large and spreading leaves, as if there might be fruit on it. To the casual reader it may seem strange at first to look for figs when it was not the season for them. He was actually not expecting to find any, but something else. This is what one encyclopedia(百科全書) stated regarding these trees.
Noting that, as verse 13 shows, our Savior did not expect to find a fig on the tree, but He was looking to find something. The tree was probably of the spring crop, and should have had at least fruit buds during this time of year. We need to bear in mind that figs were a food staple in the Middle East. Christ did not find what he was looking for on the plant and therefore cursed it.
There are two profound lessons that we can learn from this incident. The first lesson can be found within verse 14 where Christ stated, "Let no one eat fruit from you ever again." God makes an investment in every person He calls into His truth. He gives them the priceless gift of His Holy Spirit and thus He expects His followers to make good use of it and grow in spiritual character. Christians must produce spiritual fruits. The total failure to do so will result in the final punishment of being cast into the lake of fire.
The second lesson is given to us by Jesus himself in verses 20 to 24 of the same chapter. The incident of the curse of the fig tree was not a case of disappointment resulting in an outburst of impatience. It was a great and unforgettable lesson in faith delivered by the Son of God in an unusual circumstance. This incident was also an admonition(警告) to NOT be fruitless.
How?
No matter good or bad circumstance a Christian must have good spiritual fruit.