In the following passage the Apostle Paul speaks of being "alive" once and when the commandment came he "died":
"For I was alive without the law once: but when the commandment came, sin revived, and I died. And the commandment, which was ordained to life, I found to be unto death. For sin, taking occasion by the commandment, deceived me, and by it slew me" (Ro.7:9-11).
Paul is not speaking of "physical" death because he was alive physically when he wrote those words. He is speaking about breaking one of the Ten Commandments (v.7) and it was that which resulted in his "spiritual death."
In a commentary written by the faculty of Dallas Theological Seminary John A. Witmer writes:
"As a result Paul 'died' spiritually (cf. 6:23a) under the sentence of judgment by the Law he had broken...so this sin deceived him...and 'put' him 'to death' (lit., 'killed' him), not physically but spiritually" (
The Bible Knowledge Commentary; New Testament , ed. Walvoord and Zuck [Colorado Springs: Chariot Victor Publishing, 1983], 467).