There are two aspects of God or Brahman : (1) the Unmanifested (Nirgun) and (2) the Manifested (Sagun).
The Nirgun is formless, while the Sagun is with form, though both denote the same Brahman. Some prefer to worship the former, some the latter.
As stated in the Gita (chapter XII) the worship of the latter is easy and preferable. As man has got a form (body, senses, etc.), it is natural and easy for him to worship the God with form.
Our love and devotion do not develop unless we worship Sagun Brahman for a certain period of time, and as we advance; it leads us to the worship (meditation) of Nirgun Brahman.
So let us start with Sagun worship. Image, altar, fire, light, sun, water, Brahman are the seven objects of worship, but Sadguru is better than all these.
Let us, on this occasion, bring to our mind the form of Sai, Who was non-attachment Incarnate, and Who was a resting-place for His whole-hearted devotees.
SSSC ch 11
"I draw to Me, My man from far off or even across the seven Seas to Shirdi, like a sparrow with a string fastened to its feet"-Shirdi Sai Baba, Indian Spiritual Guru-God 