brightness of day. The speaker's soul transforms from the darkness of his misery to the light of his joy in loving the young man. In contrast to the useless or futile cries to God that the speaker mentions in the octet, the speaker is now able to sing "hymns" (or religious songs) to God (line 12). The speaker no longer feels that his prayers are unanswered. The speaker now has hope.
In the couplet, the final two lines of the poem, the speaker confidently and happily exclaims that he would rather be himself, as a person who is able to feel love for the young man, than to be the greatest king in the world. He is stating that having love is a greater gift than having riches or political power or prestige. Only love has the power to enrich the soul and bring light and hope to someone even in the darkest of times.
As mentioned, the sonnet is quite similar to those by Francis Petrarch. This sonnet shows the speaker moving from one extreme emotion to another. But unlike the sonnets by Petrarch, the speaker's love for the young man is not unrequited. The love is genuine and true. The love is reciprocated (or returned). So, the theme of "Sonnet 29" is not identical to those by Petrarch. The speaker in Petrarch's sonnets never experiences a reciprocated love. Whatever hopes he has are false hopes: they will not come true. In Shakespeare's poem, the speaker -- or the poet -- is declaring the power that true love brings to those who possess it.