I personally believe that every Christian who is serious about studying the Bible ought always to have at least one Bible commentary in hand to help guide them through the Scriptures and give additional and helpful insights. One of the commentaries I use, and would recommend to absolutely every Christian, is by the 18th century Puritan Matthew Henry (an immense 2,000 page volume). Henry was born in 1662 and died in 1714, and although his commentary on the Bible is now 300 years old, it is still one of the most commonly used and well respected commentaries available today. Henry wrote his commentary as both a theologian and a pastor, therefore his insights and expositions of Scripture are highly intellectual but at the same time very practical for helping all Christians to apply the Bible to their everyday living. For those who are looking for an aid to assist them in their studies of the Scriptures, this commentary by Matthew Henry is an invaluable treasure to help lead to a deeper understanding and living out of God's Word.
The main reason I first began using Henry's commentary was because who strongly endorsed it just over 100 years ago; that person being the great 19th century preacher Charles Spurgeon. Spurgeon had these words to say about Matthew Henry's commentary, "First among the mighty commentaries for general usefulness we are bound to mention the man whose name is a household word, Matthew Henry. He is the most pious and pithy, sound and sensible, suggestive and sober, terse and trustworthy... he is deeply spiritual, heavenly, profitable; finding good matter in every text, and from all deducting the most practical and judicious lessons."
*Special Note - For those who read the "KJV" there was a brand new Bible released earlier this year called "The Matthew Henry Study Bible" by Hendrickson Publishers, which has Henry's commentary notes spread throughout the KJV edition of the Bible. The notes are just a concise collection, not all of Henry's notes in their entirety. Therefore, for those who wish to have just a sprinkling of Matthew Henry's biblical insights (and who use the KJV), this study Bible would be perfect for such a purpose.
"The Bible is a sealed book to every man, learned or unlearned, till he begins to study it with a simple heart and a teachable spirit, that he may thence learn the truth and the will of God." - Matthew Henry
"Lay the Bible to heart, and receive with meekness the ingrafted word, which is able to save your souls." - Matthew Henry
"It is a wonder sinners can ever read the Bible with dry eyes." - Matthew Henry