If "Easter Wings" were actually "High School Musical, 1633," Adam would be the dumb jock and the speaker would definitely be the weak blushing nerd. That's the biggest contrast between the two stanzas, which are eerily similar. Adam "foolishly" loses his wealth; a stanza later the speaker starts out weak and only gets weaker.
And just as Adam's wealth is both material and spiritual, the speaker's thinness stems from more than sin-induced dieting. In fact, the mention of "sin" and "shame" point us in this spiritual direction. Yeah, "sicknesses" and even "sorrow" might lead someone to pine away, but do sin and shame really cause weight loss? Only if you want to slim down your soul. The speaker, burdened with Adam's inherited sin as well as his own, loses his closeness to God too.
Line 11: From the sound of it, the speaker's childhood was no walk in the park. Picnics and playing with Sue next door? Think again. The speaker's early memories are of sadness and pain. "Tender," although a common adjective to describe youth, reinforces the idea that the speaker started out vulnerable.
Lines 12-13: Too bad for the speaker, it only gets worse. It isn't really life that's beating him down, but God himself, who sends sickness and shame for his own good. Because the speaker is full of sin, he needs to endure religious punishment. According to the poem's metaphor, that punishment comes in the form of physical ailment.
Lines 14-15: As a result, the speaker becomes even weaker, bottoming out in line 15 as "most thin." The image of a physically wasted, drastically weakened speaker is a metaphor for the spiritually wasted speaker, weakened from sin.
Lines 19-20: In fact, the speaker is so weak with sin that he isn't able to act on this request alone. He wants to "combine" with God on this Easter Sunday, but he's too damaged to rise without help. Using a hawking metaphor, Herbert emphasizes that, according to him, only God can heal us and give us spiritual strength.