Paul looks at his past life as a blasphemer, but doing it ignorantly. We all have a past life. Plenty of sin, plenty of ignorant foolishness but thank God I was delivered by the acceptance of Christ.
In a following verse Paul calls himself the chief of sinners but he says that Christ came to save sinners. He claims to be a pattern of God's patience with sinners.
Next is a kind of doxology about the Lord Jesus Christ. Of course the oneness of the Father, Son and Holy Spirit. These are beautiful words. He is King eternal, immortal, invisible, all wise and only wise be glory and honor forever. Could I add to that? I will say with Paul, "Amen"!