The poet now admits that his believing that his love for the youth was as great as it could ever be was wrong: He can love the young man even more fully than he has done in the past. Comparing how things change over time to his newfound knowledge of how much his love for the youth can yet increase, the poet questions why he let time scare him into previously saying "Now I love you best" to the youth when his love for the young man grows the longer the poet knows him.
Although the poet now realizes that his love for the youth may increase even more, there is also a sense that the poet gets what he deserves rather than what he wants. His past confidence in how much he loved the youth was false, which is why he cannot say "Now I love you best": "Alas, why, fearing of Time's tyranny, / Might I not then say, 'Now I love you best' / . . . / . . . doubting of the rest?" And yet such security is exactly what the poet craves. He wants to say decisively that at the current time he loves the youth as much as he can ever love him, but "Love is a babe; then might I not say so, / To give full growth to that which still doth grow." The poet's again saying that now is the time that he most loves the youth may be detrimental, for such an expression may very well limit any future growth in the relationship.