Many preachers intentionally dress a certain way when they preach in order to enhance the message they are trying to get across. Some preachers make different decisions than others.
Some preachers change their mind over time about how they should dress on Sunday. For example, one of my favorite preachers used to wear a suit and tie every time he preached. A few years later, I saw him preach wearing black jeans and a black shirt that was not tucked in. That was quite a change! A few years after that, he was somewhere in between those two extremes—dressed in a nice pair of slacks with his shirt tucked in.
No matter how you dress, you always have to be thinking about how people will receive your message. You need to try to relate to the greatest number of people you are trying to impact.
“…I have become all things to all people so that by all possible means I might save some.”—1 Cor.9:22.