A believer with bad character is like a thorn troubling people whilst a believer with good character is like a rose; he gives fragrance to all those around him.
The alchemy of scientists is to turn dust into gold. The alchemy of the Mashaaikh is to turn thorns into roses.
If you plant a thorn in the ground nothing grows. In a Khanqah (Spiritual retreat where the Mashaikh help people with reformation), thorns come (Meaning people with bad character in need of islaah/spiritual reformation) and these thorns which stay in a Khanqah with Ikhlaas (Sincerity) grow into roses.
From the Majlis of Shaykh Dawood Seedat here