What is the primary authority in a Christian's life? in the practice of the Church?
I am not sure what is meant by a false link of study as I personally see nothing wrong with pursuing the original question to understand from whence this practice originated.
A basic Google search for the history of the practice of Lent led me to this https://www.baylor.edu/content/services/document.php/193181.pdf
"By the mid-third century, Dionysius of Alexandria speaks of a fast of up to six days practiced by the devout in his see; and the Byzantine historian Socrates relates that the Christians of Rome at some point kept a fast of three weeks.2 Only following the Council of Nicea in 325 a.d. did the length of Lent become fixed at forty days, and then only nominally. Accordingly, it was assumed that the forty-day Lent that we encounter almost everywhere by the mid-fourth century must have been the result of a gradual lengthening of the pre-Easter fast by adding days and weeks to the original one- or two-day observance.3 This lengthening, in turn, was thought necessary to make up for the waning zeal of the post-apostolic church and to provide a longer period of instruction for the increasing numbers of former pagans thronging to the font for Easter baptism. Such remained the standard theory for most of the twentieth century."
Shall it then be lawful to observe what men have framed in their own wisdom? Do we not see that it is a matter which goeth directly against God? St. Paul setteth himself against such deceivers: against such as would bind Christians to abstain from meats as God had commanded in His law. If a man say, it is but a small matter to abstain from flesh on Friday, or in Lent, let us consider whether it be a small matter to corrupt and bastardize the service of God! For surely those that go about to set forth and establish the tradition of men, set themselves against that which God hath appointed in His Word, and thus commit sacrilege.
~ John Calvin https://www.the-highway.com/The_Word.html