1.  ean = if haply, if so be that, from ei (No. 2) and an, haply, perchance. The exact condition is shown by the Mood of the verb with which it is used:

 a.   Followed by the Indicative Mood (with the Present Tense), it expresses the condition simply; without any reference to its being decisive by experience, or by the event, as in 1John 5:15, elsewhere, and in the Papyri.

 b.  Followed by the Subjunctive Mood, it expresses a hypothetical but possible condition, contingent on circumstances which the future will show (John 7:17).

  2.  ei = if.  Putting the condition simply.

 a.  Followed by the Indicative Mood, the hypothesis is assumed as an actual fact, the condition being unfulfilled, but no doubt being thrown upon the supposition (1Cor. 15:16).

 b.  Followed by the Optative Mood, it expresses an entire uncertainty; a mere               

assumption or conjecture of a supposed case (Acts 17:27. 1Peter 3:14).

 c.  Followed by the Subjunctive Mood, like No. 1. b; except that this puts the condition with more certainty, and as being more dependent on the event (1Corinthians 14:5).

  For two illustrations, see Acts 5:38, 39. "If this counsel or this work be of men (1. b, a result which remains to be seen) . . . but if it is of God (1. a, which I assume to be the case)", etc.
  John 13:17. "If ye know these things (2. a, which I assume to be the fact) happy are ye if ye do them (1. b, a result which remains to be seen)".

  Note four "ifs" in Colossians, "if ye died with Christ" (2:20); and "if ye were raised with Christ" (3:1), both of which are No. 2. a (assuming the fact to be true); "if any man have a quarrel" (3:13); "if he come to you" (4:10), both of which are No. 1. b, being uncertainties.
  One other "if" in Colossians is 1:23: "If ye continue in the faith" (eige = if indeed, a form of 2. a), which ye will assuredly do.