In the Jewish literature, exercises from the thirteenth century involved having the mind dwell upon the names of God or the letters that make up the name of God. Rabbi Abulafia developed a system of meditating upon letters of the Hebrew alphabet as constituents of God’s name. Rabbi Abulafia used the letters of God’s name because the name is absolute. Gershom G. Scholem described Abulafia’s teaching as similar to Yoga. He writes about Abulafia’s teachings as follows.
… teachings represent but a Judaized version of that ancient spiritual technique which has found its classical expression in the practices of the Indian mystics who follow the system known as Yoga. To cite only one instance out of many, an important part in Abulafia’s system is played by the technique of breathing; now this technique has found its highest development in the Indian Yoga, where it is commonly regarded as the most important instrument of mental discipline. Again, Abulafia lays down certain rules of body posture, certain corresponding combinations of consonants and vowels, and certain forms of recitation, and in particular some passages of his book “The Light of the Intellect” give the impression of a Judaized treatise on Yoga. The similarity even extends to some aspects of the doctrine of ecstatic vision, as preceded and brought about by these practices.