Simple explanation of a difficult passage related with "mind", Buddha and visions from the Contemplation Sutra

I decided to give a short explanation of the following passage from the Contemplation Sutra that many find it difficult to understand or have the tendency to misinterpret it:

“Buddha Tathagatas have cosmic bodies, and so enter into the meditating mind of each sentient being. For this reason, when you contemplate a Buddha, your mind itself takes the form of His thirty-two physical characteristics and eighty secondary marks.

Your mind produces the Buddha’s image and is itself the Buddha. The ocean of perfectly and universally enlightened Buddhas thus arises in the meditating mind. For this reason, you should single-mindedly concentrate and deeply contemplate the Buddha Tathagata, Arhat, and Perfectly Enlightened One.”