The incense stick is the symbol of self-consecration. Incense sticks are associated with adoration.
Consecration is a process by which one trains the consciousness to give oneself to the Divine. The general principle of self-consecration and self-giving is the same for all in the yoga, but each has his own way of consecration and self-giving.
It is a fact always known to all yogis and occultists since the beginning of time, in Europe and Africa as in India, that wherever yoga or Yajna is done, there the hostile Forces gather together to stop it by any means. It is known that there is a lower nature and a higher spiritual nature, it is known that they pull different ways and the lower is strongest at first and the higher afterwards. It is known that the hostile Forces take advantage of the movements of the lower nature and try to spoil through them, smash or retard the siddhi. It has been said as long as long ago as the Upanishads (hard is the path to tread, sharp like a razor's edge); it was said later by Christ 'hard is the way and narrow the gate by which one enters into the kingdom of heaven' and also 'many are called, few chosen' because of these difficulties. But it has also been known that those who are sincere and faithful in heart and remain so and those who rely on the Divine will arrive in spite of all difficulties, stumbles or falls.