In the Old Testament, we find that each prophet had a unique burden given to him by God - but all of them were concerned about the lack of holiness among God's people.
The burden God lays on your heart is almost always an indication of the ministry He has planned for you. So, wait on the Lord to receive a burden from Him. If you serve the Lord without a burden, you will get bored with the Lord's work after a while, and you are likely to end up seeking after money, man's honour or earthly comfort. It is unfortunate that many who claim to be serving the Lord today have no God-given burden for their ministry.
God may give one man a burden to work among children and another a burden for evangelism. Yet another may be given a burden to teach God's people. God gives different burdens to different members of Christ's body. We must not imitate someone else's ministry or try to have his burden. Don't force others to have your burden; and don't allow anyone else to give you his burden. Let God Himself give you a burden -the one He has planned for you.
Many people have urged me to have a burden for their particular ministry - usually evangelism. But I have always resisted such pressures. I am not interested in having the burden God has given to another. God has given me a specific burden and I am determined that that is the only ministry I will fulfil. The prophets never allowed anyone to sidetrack them from the burden and the ministry God gave them.
If you don't have any burden at all, you must go to God and ask Him to give you a burden. He has a definite task for you to fulfil in the body of Christ and you must know what it is. Many preachers wander from one ministry to another - joining whichever Christian organisation offers them the highest salary.
For example, they may start with an apparent "burden" for a radio ministry. But if some child-evangelism organization then offers them a higher salary, they suddenly develop a "burden" for child-evangelism! A little later, if a Christian literature organisation offers them a still higher salary, their "burden" suddenly shifts to a literature ministry!! Such preachers are not serving the Lord. They are religious men who are engaged in Babylonian "businesses". When God gives you a burden, you cannot give that up just because some organisation offered you better earthly benefits.