諸經要集 4.105

4.105

又三千威儀云。燒香著佛前。有三事。一易中故香。二當自出香。三當布與人。具香鑪有三事。一當先倒去故灰。拾取中香聚一面。二當拭令淨乃著火。還取故香著中。三火著時熾然。不得吹令炭滅。

The Sanqian weiyi also states: Burning incense before the Buddha involves three things: first, replace the old incense inside; second, take out the incense oneself; third, distribute it to others. Preparing the censer involves three things: first, pour out the old ashes first, gather the unburnt incense inside, and set it to one side; second, wipe it clean before adding fire, then take back the old incense and place it inside; third, when the fire is lit and blazes, one must not blow on it and extinguish the embers.