Be instructed, O man, in things that are here below, and be not curious nor overmeddling about heaven. And would it were heaven, and not the Lord of heaven! Do you not know the earth from which you were brought forth, in which you were nourished, which thou inhabitest, on which you walk, without which you can not even breathe; and are you curious about things so far removed? Truly “man is vanity.” And if any one should bid you descend into the deep, and trace out things at the bottom of the sea, you would not tolerate the command.
But, when no one compels you, you are willing of yourself to fathom the unsearchable abyss? Do not so, I beseech you. But let us sail upwards, not floating, for we shall soon be weary, and sink; but using the divine Scriptures, as some vessel, let us unfurl the sails of faith. If we sail in them, then the Word of God will be present with us as our Pilot. But if we float upon human reasonings, it will not be so. For to whom of those who float, is a Pilot present? So that the danger is twofold, in that there is no vessel, and that the Pilot is absent.
For if even the boat without a pilot is unsafe, when both are wanting, what hope is there of safety? Let us not then throw ourselves into manifest danger, but let us go upon a safe vessel, having fastened ourselves by the sacred anchor. For thus we shall sail into the tranquil haven, with much merchandise, and at the same time with great safety, and we shall obtain the blessings laid up for them that love Him, in Christ Jesus our Lord, with whom, to the Father, together with the Holy Spirit, be glory, power, honor, now and always and world without end. Amen.
Source: Homilies on First Thessalonians (New Advent)