And I was delivered out of the mouth of the lion. This may either mean that he was delivered from Nero, compared with a lion, or, literally, that he was saved from being thrown to lions in the amphitheatre, as was common in Rome. .
(3.) It is not uncommon in the Scriptures to compare tyrants and persecutors with ravenous wild beasts. Comp. Ps 22:13,21; Jer 2:30. Nero is called a lion by Seneca, and it was usual among heathen writers to apply the term in various senses to princes and warriors. See Grotius, in loc. The common interpretation here has been, that this refers to Nero, and there is no improbability in the interpretation. Still, it is quite as natural to suppose, that the punishment which had been appointed for him, or to which he would have been subjected, was, to be thrown to lions, and that in some way, now unknown to us, he had been delivered from it. Paul attributes his deliverance entirely to the Lord; but what instrumental agency there may have been, he does not specify. It seems probable that it was his own defence; that he was enabled to plead his own cause with so much ability, that he found favour even with the Roman emperor, and was discharged. If it had been through the help of a friend at court, it is hardly to be supposed that he would not have mentioned the name of him to whom he owed his deliverance.
{c} "Lord stood" Mt 10:19; Ac 23:11
{d} "mouth of the lion" Ps 22:21 -- Albert Barnes