Weep Not For Me

Weep not for me, wife and children dear;
Think on the dust that lieth here;
And when this you see, remember me,
Prepare for death and follow me.

Michael Thomas Brew

I can not find a specific reference, but there is a similar verse in the book "Rambles in forfarshire", and are a record of epitaphs found in the churchyard of Inverarity.
"Stand still, reader, shed a tear,
Think on the dust that lieth here;
And when you read this state of mine.
Think on the glass that runs for thine,
And on this world put not your trust,
Remember you must come to dust."

I find these epitaphs slightly odd, as they are quite ominous. I am unsure why someone would choose to have words such as "Prepare for death and follow me".