If we say that we (hēmartēkamen | ἡμαρτήκαμεν | perf act ind 1 pl) have (hēmartēkamen | ἡμαρτήκαμεν | perf act ind 1 pl) not sinned (hēmartēkamen | ἡμαρτήκαμεν | perf act ind 1 pl), we make him a liar and his word is not in us.
Reference
1 John 1:10
Sequence
31