Thanks for that.Warren Wiersbe…
"It is finished!" is one word in the Greek text—tetelestai. The word was a common one and was used by merchants to mean "The price is all paid!" Shepherds and priests used it when they found a perfect sheep, ready for sacrifice; and Christ died as the perfect lamb of God. Servants, when their work was completed, would use this word when reporting to their masters. Christ, the obedient Servant, had finished the work the Father gave Him to do. Christ willingly and deliberately gave up His life; He laid down His life for His friends. (Wiersbe, W. W. Wiersbe's Expository Outlines on the New Testament. Wheaton, Ill.: Victor Books)
John MacArthur writes that It is Finished…
was a shout of triumph; the proclamation of a victor. The work of redemption that the Father had given Him was accomplished: sin was atoned for (He 9:12-note; He 10:12-note), and Satan was defeated and rendered powerless (He 2:14-note; cf. 1Pe 1:18, 19-note, 1Pe 1:20-note; 1Jn 3:8). Every requirement of God's righteous law had been satisfied; God's holy wrath against sin had been appeased (Ro 3:25-note; He 2:17-note; 1Jn 2:2; 4:10); every prophecy had been fulfilled. Christ's completion of the work of redemption means that nothing needs to be nor can be added to it. Salvation is not a joint effort of God and man, but is entirely a work of God's grace, appropriated solely by faith (Eph. 2:8, 9-note). His mission accomplished, the time had come for Christ to surrender His life. (MacArthur New Testament Commentary – John 12-21)
Andrew Murray;
Perhaps the meaning that Jesus had foremost in His mind when He uttered the word tetelestai was related to its secular use in the context of payment of debts. When someone had a debt in ancient times and it was paid off, they would write "tetelestai" on the certificate signifying "Paid in Full". When He gave Himself on the cross, Jesus fully met the righteous demands of a holy law; He paid our debt in full. None of the Old Testament sacrifices could take away sins. Their blood only covered sin. But the Lamb of God shed His blood, (for the redemption of the transgressions that were committed under the first covenant, Heb 9:15-note) and that blood (and only that blood) can take away the sins of the world (Jn 1:29; He 9:24-note, He 9:25, 26-note, He 9:27, 28-note).
Also, J.C. Ryle wrote: 'One comfortable thought , at all events, stands out most clearly......We rest our souls upon a finished work .if we rest them on the work of the Lord Jesus Christ.......We may lean back on the thought that we have a a Saviour who has done all, paid all, accomplished all, performed all that is necessary for our salvation.'