For a number of years, I have read and heard, and even thought it myself, that tribulation is primarily about persecution.

However, the following three scriptures kind of shows that they may even be two different things, although possibly related.

Matthew 13:21 Yet hath he not root in himself, but dureth for a while: for when tribulation or persecution ariseth because of the word, by and by he is offended.

Romans 8:35 Who shall separate us from the love of Christ? shall tribulation, or distress, or persecution, or famine, or nakedness, or peril, or sword?

II Thessalonians 1:4 So that we ourselves glory in you in the churches of God for your patience and faith in all your persecutions and tribulations that ye endure:

Can persecution be considered a form of tribulation, or are they definitely two separate things?

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