A — 1: ἀσθενής
(Strong's #772 — Adjective — asthenes — as-then-ace' )

lit., "strengthless" (see IMPOTENT), is translated "weak," (a) of physical "weakness," Matthew 26:41; Mark 14:38; 1—Corinthians 1:27; 4:10; 11:30 (a judgment upon spiritual laxity in a church); 2—Corinthians 10:10; 1—Peter 3:7 (comparative degree); (b) in the spiritual sense, said of the rudiments of Jewish religion, in their inability to justify anyone, Galatians 4:9; of the Law, Hebrews 7:18; in Romans 5:6 , RV , "weak" (AV, "without strength"), of the inability of man to accomplish his salvation; (c) morally or ethically, 1—Corinthians 8:7,10; 9:22; (d) rhetorically, of God's actions according to the human estimate, 1—Corinthians 1:25 , "weakness," lit., "the weak things of God." See FEEBLE , SICK.

A — 2: ἀδύνατος
(Strong's #102 — Adjective — adunatos — ad-oo'-nat-os )

lit., "not powerful," is translated "weak" in Romans 15:1 , of the infirmities of those whose scruples arise through lack of faith (see Romans 14:22,23 ), in the same sense as No. 1 (c); the change in the adjective (cp. Romans 14:1 ) is due to the contrast with dunatoi, the "strong," who have not been specifically mentioned as such in ch. 14. See IMPOSSIBLE.

B — 1: ἀσθενέω
(Strong's #770 — Verb — astheneo — as-then-eh'-o )

"to lack strength," is used in much the same way as A, No. 1, and translated "being ... weak" in Romans 4:19 , AV (RV, "being weakened"); 8:3; 14:1,2 (in some texts, 1—Corinthians 8:9 ); 2—Corinthians 11:21,29 (twice); 12:10; 13:3,4,9. See DISEASED , IMPOTENT , SICK.

C — 1: ἀσθένεια
(Strong's #769 — Noun Feminine — astheneia — as-then'-i-ah )

for which see INFIRMITY , is rendered "weakness," of the body, 1—Corinthians 2:3; 15:43; 2—Corinthians 11:30 , RV; 12:5 (plural, RV),9,10, RV; Hebrews 11:34; in 2—Corinthians 13:4 , "He was crucified through weakness" is said in respect of the physical sufferings to which Christ voluntarily submitted in giving Himself up to the death of the Cross.