When he was younger he was under the influence of people like BK, MA..
He later on emerged as a secular ruler. He does not seem to be a devout Muslim. But the fact that he introduced a syncretic religion only shows his religious tolerance and the fact that he is very secular even for the present times.
Obviously, during his period this move will be considered as blasphemous.
Wikepidia:
Din-i-Ilahi prohibits lust, sensuality, slander and pride, considering them sins. Piety, prudence, abstinence and kindness are the core virtues. The soul is encouraged to purify itself through yearning of God. Celibacy is respected and the slaughter of animals is forbidden. There are neither sacred scriptures nor a priestly hierarchy in this religion.
^^ Only shows that it was all done to promote religious tolerance and how open minded Akbar really was.