John Milton's 'On His Twenty-Third Birthday'

How soon hath Time, the subtle thief of youth,
Stol'n on his wing my three-and-twentieth year!
My hasting days fly on with full career,
But my late spring no bud or blossom shew'th.
Perhaps my semblance might deceive the truth
That I to manhood am arriv'd so near;
And inward ripeness doth much less appear,
That some more timely-happy spirits endu'th.
Yet be it less or more, or soon or slow,
It shall be still in strictest measure ev'n
To that same lot, however mean or high,
Toward which Time leads me, and the will of Heav'n:
All is, if I have grace to use it so
As ever in my great Task-Master's eye

This sonnet – ‘On His Twenty-Third Birthday’ was written by John Milton when he was still a student at Cambridge. The sonnet shows a sense of dedication to a great mission, and the spirit of resignation to the Will of God. His life’s great ‘task’ requires inward ripeness. This is the passion of a great soul for noble achievement.
The poet says that time like a clever thief has very quickly and quietly taken away twenty three years of his life. The poet feels that time is fleeting but he still does not have to his credit some work of achievement as a poet.
In the next stanza, the poet says that his outward appearance might appear deceptive and go against the truth. He says that he has almost reached his manhood and has a mature look outwardly but has too little maturity of mind. The inner maturity of mind is more important for a poet than the physical one. That is why the poet envies his friends whose spiritual and physical developments go hand in hand.
The poet seems to be reconciling himself to the situation. He says that the inner maturity, in less or more quantity will surely come to him one day may be sooner or later. This would happen by the will of God. He shows his belief in God who decides all things for the best. The poet decides that when he acquires his intellect fully, he would use it for the service of God by composing religious poetry. This shows that the poet has high seriousness of purpose.