Brethren, Rejoice in the Lord always: again, I say, rejoice. Let your modesty be known to all men. The Lord is nigh. Be nothing solicitous: but in every thing, by prayer and supplication, with thanksgiving, let your petitions be made known to God. And the peace of God, which surpasseth all understanding, keep your hearts and minds in Christ Jesus our Lord.
Verse 6. But in everything by prayer, &c. By the Greek, the sense and construction cannot be in every prayer; but in every thing, in all circumstances, have recourse to prayer. Wi.
From the Encyclical "Mirari vos arbitramur," Aug. 15, 1832
Having embraced with paternal affection those especially who have applied their mind particularly to the sacred disciplines and to philosophic questions, encourage and support them so that they may not, by relying on the powers of their own talents alone, imprudently go astray from the path of truth into the way of the impious. Let them remember “that God is the guide of wisdom and the director of the wise” [cf. Wisd. 7:15], and that it is not possible to learn to know God without God, who by means of the Word teaches men to know God. It is characteristic of the proud, or rather of the foolish man to test the mysteries of faith “which surpasseth all understanding” [Phil. 4:7] by human standards, and to entrust them to the reasoning of our mind, which by reason of the condition of our human nature is weak and infirm.