Don't be Sad
If you really cannot do something, leave it
I used to give the Friday sermon in the city of Abha. Most of my sermons dealt with different aspects of the Prophet's life, and this became something of a specialty with me and was something with which I felt comfortable. Somebody had asked me to give a sermon about the increasing tendency of extravagant dowries. I was loath to comply with this request because I felt more comfortable in speaking about the biography of the Prophet (bpuh). Nevertheless, I gave an impromptu sermon on the requested topic. I quoted verses from the Qur'an and sayings of the Messenger of Allah (bpuh). I was covering the topic in a desultory manner, and as I was speaking, I felt the sweat trickle down my forehead. After my sermon was over, I felt that I had done a very poor job in speaking about the subject, and so I resolved to stick to what I excelled at.
(...nor am I one of the Mutakallifoon [those who pretend and fabricate things which do not exist].) (Quran 38: 86)
Every one of us should work in a field that he is skilled in. The Prophet (Blessings and Peace be upon him) said:
"Indeed, Allah loves for each of you, when he works at something, to perfect it."