Looks like it’s Erasmus… see below:

“It would, however, be erroneous to describe the Reformation as a mainly political event or to see in Luther a selfish philistine and materialist. Kierkegaard, with too little knowledge of the real Luther, rejected him as a dreary, narrow bourgeois, a deplorable projection of Danish mid-nineteenth century Lutheran church life into the sixteenth century. The Reformation activated a great religious fervor, especially among the nonintellectuals. The main figures of Humanism—Erasmus, Reuchlin, Pirckheimer, Adelsmann—were enthusiastic about Luther’s early moves but parted with him decidedly when they saw his final direction; the university cities too were very much holding back and showed no enthusiasm.[22]”

I am not at all sure that there is one “humanist” philosophy, but I am confident that the one you cite is a poor enunciation. Humanism begins with the presumption that knowledge of human kind and his environs begins with man and not some presumed external being. Humanist ethics would indeed argue that earthly good was relevant to ethics but that some future salvation is/was not. But this is also true of many theologies which see future salvation as a gift not determined by “good works” and argue that good works — to the extent that anything humans do can be called good — are relevant only to relations here on earth.

Since Martin Luther believed deeply in Christian Salvation, he would not be one likely to lead a humanist philosophy or any works based philosophy. We know little about the background of Ferdinand Magellan, but we do know that he attempted, sometimes successfully, to convert native peoples to Catholicism which suggests a spiritualist focus. Desiderius Erasmus was the only one of the three to formally espouse any form of humanism in his writings.

I wouldn’t really consider Luther or Erasmus humanists, per se, and I don’t know enough about Magelan to say one way or the other. When you’re talking about the world being lit on fire by these guys, look at what they contributed to society, then pick the one that is most interesting to you; that’ll will make it easier to pick a topic.