Keep in mind John Calvin’s book Institutes of Christian Religion was updated a total of 5 times 1536, 1539,1543, 1550, and 1559.
Take the time to read Phillip Melancthon’s Loci Communes
, Huldyrch Zwingli’s Commentary on True and False Religion, Martin Bucer’s works and Martin Luther’s works. Before criticizing John Calvin’s works. The TULIP was a good part of Christianity for many years. The scholastic theologians argued with one another for years over the Catholic Church and the Protestant Reformation and the Catholic Counter Reformation.
The church that we have have today is an aspect of what came about over the years of the arguments. Liberalism of the church came about by yet another movement that spread through the world over other aspects of Christian thought.
Also take a look at Augustine’s City of God, Aquinas’ Summa Theologica.
Remember Martin Luther started a the Protestant Reformation by nailing his 95 Theses to the door of Wittenberg. He wanted a debate with other church scholars over theological abuses and heretical view points.
Calvin was influenced by Luther, Zwingli, Bucer and melancthon.
But keep in mind Calvin was a catholic theologian whom became a lawyer and became a protestant theologian too. Calvin dedicated his first Christian Institutes to King Francis of France because the Catholic King was killing the Hugenounts (Protestant) believers in droves.
Obviously poorly catechized!