πεποίθησις, -εως, ἡ (< πείθω), [in LXX: 4Ki.18:19 (בִּטָּחוֹן)* ;] confidence: Refs 2Co.1:15 3:4 10:2, Eph.3:12; before εἰς, 2Co.8:22; ἐν, Php.3:4 (the word is condemned by the Atticists, see Rutherford, NPhr., 355).† (AS)
Thayer:
1) trust, confidence, reliance
πεποίθησις
pepoithēsis
pep-oy'-thay-sis
From the perfect of the alternate of G3958; reliance
πάσχω, πάθω, πένθω
paschō pathō penthō
pas'-kho,path'-o,pen'-tho
Apparently a primary verb (the third form used only in certain tenses for it); to experience a sensation or impression (usually painful)
KJV Usage: feel, passion, suffer, vex.
G3663 ὁμοιοπαθήςὁμοιοπαθής
homoiopathēs
hom-oy-op-ath-ace'
From G3664 and the alternate of G3958; similarlyaffected
KJV Usage: of (subject to) like passions.
G3806 πάθοςπάθος
pathos
path'-os
From the alternate of G3958; properly suffering (“pathos”), that is, (subjectively) a passion (especially concupiscence)
KJV Usage: (inordinate) affection, lust.
G3997 πένθοςπένθος
penthos
pen'-thos
Strengthened from the alternate of G3958; grief
KJV Usage: mourning, sorrow.
G4310 προπάσχωπροπάσχω
propaschō
prop-as'-kho
From G4253 and G3958; to undergo hardship previously
KJV Usage: suffer before.
G4841 συμπάσχωσυμπάσχω
sumpaschō
soom-pas'-kho
From G4862 and G3958 (including its alternate); to experiencepainjointly or of the samekind (specifically persecution; to “sympathize”)