Reference for Yevamot 142:19

ובמדבר מאי טעמא לא מהול איבעית אימא משום חולשא דאורחא

but all the people that were born etc.?<span class="x" onmousemove="('comment',' In the wilderness&nbsp;… had not been circumcised, Josh. V, 5. ');">³⁰</span> — If so,<span class="x" onmousemove="('comment',' If the instruction to circumcise applied to the non-circumcised only. ');">³¹</span> why the expression. 'Again!' Consequently<span class="x" onmousemove="('comment',' Lit., 'but not'? ');">³²</span> it must apply to the uncovering of the corona.<span class="x" onmousemove="('comment',' I.e., a second circumcision for those who were already, but not properly, circumcised. ');">³³</span> Why, then,<span class="x" onmousemove="('comment',' Since the expression, 'Again', is used for the purpose of an exposition. ');">³⁴</span> the expression, 'A second time?'<span class="x" onmousemove="('comment',' Josh. V, 2. As 'Again', so should 'A second time' also he expounded. ');">³⁵</span> — To compare the termination of the circumcision with its commencement; as the commencement of the circumcision is essential<span class="x" onmousemove="('comment',' Lit., 'prevents'; unless circumcision was performed the Paschal lamb may not be eaten. ');">³⁶</span> so is the termination of circumcision<span class="x" onmousemove="('comment',' The uncovering of the corona. ');">³⁷</span> essential;<span class="x" onmousemove="('comment',' Cf. supra n. 7. ');">³⁸</span> for we learned, 'These are the shreds which render circumcision invalid: Flesh which covers the greater part of the corona; and [a priest whose circumcision was so defective] is not permitted to eat terumah'; and Rabina, or it might be said, R. Jeremiah b. Abba, stated in the name of Rab: Flesh which covers the greater part of the height of the corona.<span class="x" onmousemove="('comment',' Shab. 137a and supra 47b q.v. for notes. ');">³⁹</span> Why were they not circumcised in the wilderness? — If you wish I might say: Because of the fatigue of the journey;

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