Proofs for God: Justification

I think most readers of this blog are aware that philosophically oriented rabbis, of the Maimonidean school, have advocated proving God's existence. However, others consider it to be unnecessary and maybe even improper (see this post). I came across an interesting source that promotes such philosophical contemplation: The classic commentary on the Talmud, Maharsha.

In his commentary to Ta'anis 2a (Chiddushei Aggados, sv. kesiv hakha), the Maharsha writes that it is proper to investigate and acquire knowledge of the world and its creation. However, whatever you fail to understand you should attribute to the limits of your own understanding. In a later comment (4a sv. af kn"y), he makes it clear that the earlier comment also applies to God's existence. Maharsha then expands on this and says that after Jews suffer for their sins, it is proper for them to return to God and to pursue complete knowledge and understanding of God's existence. He quotes the Chovos Ha-Levavos (I'm not sure where) as saying that the more you ponder God's existence, the stronger your knowledge becomes.