The hours of prayer

Now, if some assign definite hours for prayer— as, for example, the third, and sixth, and ninth— yet the Gnostic prays throughout his whole life, endeavoring by prayer to have fellowship with God. And, briefly, having reached to this, he leaves behind him all that is of no service, as having now received the perfection of the man that acts by love. But the distribution of the hours into a threefold division, honored with as many prayers, those are acquainted with, who know the blessed triad of the holy abodes.

Clement of Alexandria
The Stromata, Book VII
Chapter VII

The thoughts of the saints cover the world

And should any one say that the voice does not reach God, but is rolled downwards in the air, yet the thoughts of the saints cleave not the air only, but the whole world. And the divine power, with the speed of light, sees through the whole soul.

Clement of Alexandria
The Stromata, Book VII
Chapter VII

Unwritten Apostolic tradition has been handed down

Now that the Savior has taught the apostles, the unwritten rendering of the written [Scripture] has been handed down also to us, inscribed by the power of God on hearts new, according to the renovation of the book.

Clement of Alexandria
The Stromata, Book VI
Chapter XV

Prophecy is obscure unless sought in love

But prophecy does not employ figurative forms in the expressions for the sake of beauty of diction. But from the fact that truth appertains not to all, it is veiled in manifold ways, causing the light to arise only on those who are initiated into knowledge, who seek the truth through love.

Clement of Alexandria
The Stromata, Book VI
Chapter XV

God gave both the Hebrew covenants and Greek philosophy

And further, that the same God that furnished both the Covenants was the giver of Greek philosophy to the Greeks, by which the Almighty is glorified among the Greeks, he shows.

…But as the proclamation [of the Gospel] has come now at the fit time, so also at the fit time were the Law and the Prophets given to the Barbarians, and Philosophy to the Greeks, to fit their ears for the Gospel.

Clement of Alexandria
The Stromata, Book VI
Chapter V & VI