Anguish (sunochēs). Ablative case after ek (out of). Old word from sunechō, to hold together. So contraction of heart (Cicero, contractio animi), a spiritual angina pectoris. In N.T. only here and Luk 21:25.
With many tears (dia pollōn dakruōn). He dictated that letter “through tears” (accompanied by tears). Paul was a man of heart. He writes to the Philippians with weeping (klaiōn) over the enemies of the Cross of Christ (Phi 3:18). He twice mentions his tears in his speech at Miletus (Act 20:19-31).
But that ye might know the love (alla tēn agapēn hina gnōte). Proleptic position of agapēn and ingressive second aorist active subjunctive gnōte, come to know.