I cannot imagine a God who rewards and punishes the objects of his creation, whose purposes are modeled after our own — a God, in short, who is but a reflection of human frailty. Neither can I believe that the individual survives the death of his body, although feeble souls harbor such thoughts through fear or ridiculous egotism. It is enough for me to contemplate the mystery of conscious life perpetuating itself through all eternity, to reflect upon the marvelous structure of the universe which we can dimly perceive, and to try humbly to comprehend even an infinitesimal part of the intelligence manifested in nature.

Albert Einstein (1879-1955) German-American physicist
“What I Believe,” Forum and Century (Oct 1930)
    (Source)

Einstein crafted and recrafted his credo multiple times in this period, and specifics are often muddled by differing translations and by his reuse of certain phrases in later writing. The Forum and Century entry appears to be the earliest. Some important variants:

I cannot conceive of a God who rewards and punishes his creatures, or has a will of the kind that we experience in ourselves. Neither ca I nor would I want to conceive of an individual that survives his physical death; let feeble souls, from fear or absurd egoism, cherish such thoughts. I am satisfied with they mystery of the eternity of life and with the awareness and a glimpse of the marvelous structure of the existing world, together with the devoted striving to comprehend a portion, be it ever so tiny, of the reason that manifests itself in nature.

— "The World As I See It [Mein Weltbild] [tr. Bargmann (1954)]

I cannot conceive of a God who rewards and punishes his creatures, or has a will of the type of which we are conscious in ourselves. An individual who should survive his physical death is also beyond my comprehension, nor do I wish it otherwise; such notions are for the fears or absurd egoism of feeble souls. Enough for me the mystery of the eternity of life, and the inkling of the marvellous structure of reality, together with the single-hearted endeavor to comprehend a portion, be it never so tiny, of the reason that manifests itself in nature.

— "The World As I See It [Mein Weltbild] [tr. Harris (1934)]

To me it suffices to wonder at these secrets and to attempt humbly to grasp with my mind a mere image of the lofty structure of all there is.

[Es ist mir genug, diese Geheimnisse staunend zu ahnen und zu versuchen, von der erhabenen Struktur des Seienden in Demut ein mattes Abbild geistig zu erfassen.]

— Reduced variant in "My Credo Mein Glaubensbekenntnis]" (Aug 1932)