A.T. Robertson Commentary Matthew 27:43

"He trusteth on God; let him deliver him now, if he desireth him: for he said, I am the Son of God." — Matthew 27:43 (ASV)

Let him deliver him now (ρυσασθω νυν). They add the word "now" to Ps 21; 22:8. That is the point of the sneer at Christ's claim to be God's son thrown in his teeth again and at the willingness and power of God to help his "son." The verb θελω here may mean

love as in the Septuagint (Psalms 18:20; Psalms 41:12) or "cares for" (Moffatt), "gin he cares ocht for him" (Braid Scots).